WHO Recommended Surveillance Standards
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WHO Recommended
Surveillance Standards - extracted text
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WHO/EMC/DIS/97.1
Distr.: Limited
Original: English
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WHO Recommended
Surveillance Standards
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This document has been produced jointly by the following
divisions and programmes of WHO:
ASD
AFRO/OCP
CHD
CTD
EMC
. FSF
GPV
GTB
and by UNAIDS
4
World Health Organization
HST
LEP
Table of Contents
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Acknowledgements.............................................................................................
Acronyms............................................................................................................
Introduction.........................................................................................................
National Plans for Communicable Disease Surveillance...................................
Explanatory Notes..............................................................................................
Sample Format....................................................................................................
Communicable Disease Surveillance Activities by WHO Policy and Division.
Cnmmnnicable Disease Contacts in Regional Offices.......................................
Diseases
e-
£
/ AIDS.......................................
f Anthrax...................................
Bacillary dysentery................
5 Brucellosis..............................
Cholera...................................
m Creutzfeldt-Jakob disease.......
Dengue ...................................
Diphtheria...............................
M Dracunculiasis........................
Ebola-Marburg viral diseases.
Japanese encephalitis..............
Lymphatic filariasis...............
Acute viral hepatitis...............
HIV infection..........................
X Influenza................................
Lassa fever..............................
. Legionellosis...........................
^■Cutaneous leishmaniasis........
Leishmania/HIV co-infections
Visceral leishmaniasis............
Leprosy...................................
Leptospirosis..........................
Malaria...................................
Measles...................................
Meningococcal disease...........
Viral meningitis......................
Neonatal tetanus......................
'*■ Onchocerciasis.......................
Pertussis..................................
Plague....................................
Poliomyelitis...........................
Rabies....................................
Salmonellosis..........................
Schistosomiasis.......................
y Scrub typhus...........................
Syphilis..................................
v African trypanosomiasis.......
** American trypanosomiasis ...
Tuberculosis..........................
y Yellow fever..........................
WHO Recommended Surveillance Standards
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October 97
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Syndromes
Acute lower respiratory tract infections (aLRTI) and Pneumonia
Acute watery diarrhoea
Acute bloody diarrhoea
Sexually transmined diseases (Genital ulcer syndrome)
Sexually transmitted diseases (Urethral discharge syndrome)
Sexually transmined diseases (Vaginal discharge syndrome).
113
115
117
119
...... 121
...... 123
Public Health Issues
v Antimicrobial resistance .......
Anti-tuberculosis drug resistance
Foodbome diseases
125
127
129
Annex 1
Surveillance Definitions ...
>, Epi Info
131
134
WHO Recommended Surveillance Standards
October 97
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Acknowledgements
The World Health Organization would like to acknowledge the support of:
The Government of the United Kingdom
and
The Government of Ireland
in the production of this document
>
WHO Recommended Surveillance Standards
October 97
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—
Fig 1 shows a case where Leptospirosis is not perceived as a prionty and is not subject to surveillance
activities. However, bacterial meningitis, which is perceived as a priority disease is not subiect to
surveillance activities- and this should be remedied.
P
V
'
subject to
Figure 1: Sample Gap Analysis in National Surveillance Assessment
Diseases
Priority
Existing
surveillance
activities
Poliomyelitis
Leptospirosis
National
Bacterial meningitis
Yellow Fever
co-ordination
Malaria
Tuberculosis
■ = Yes
surveillance gap
WHO Recommended Surveillance Standards
October 97
- No
8
Explanatory Notes
This document attempts to identify the key activities and tasks that are associated with the
surveillance of a range of communicable diseases. To avoid confusion, administrative level names
(e.g. district, province ) are not used. Instead, an attempt has been made to break down the
surveillance activities into functional levels, concentrating on the various activities that would usually
be carried out at each level (i.e. peripheral, intermediate, central). It is important to note that this
represents only a prototype that would have to be adapted to reflect the structure and level of
sophistication of existing health services. No matter what structure is decided upon, each level must
have adequate resources and receive appropriate training.
Figure 2: Schema for information flow in Communicable Disease
Surveillance
Peripheral level
Intermediate level
Central level
Ministry
of Health
Regional/lntemational level
WHO
National epidemiological
bulletin; Electronic media
________________
Weekly Epidemiological
Record: Regional Bulletin;
Electronic media
-
The peripheral level: is the first point of contact of an ill person with the health services. The
patient is usually seen by a primary care physician, clinical officer or nurse. Usually, it is at this level
that the first opportunity for epidemiological surveillance occurs. However, it must be remembered that
this is only one of many tasks. The staff at this level are unlikely to have epidemiological training and
may in fact see the recording and reporting of information on cases as administrative and unimportant.
The situation is made worse by case definitions that are confusing and difficult to apply and by having
an excessive number of reportable diseases.
In order to be successful, the collection of information must be simple and useful locally. To
this end a limited number of easily recognisable diseases or syndromes should be decided upon.
These should not normally involve extensive confirmatory procedures (unless very important) and the
principle should be the reporting to intermediate level of suspected rather than confirmed disease. The
method of recording should be in harmony with clinical record keeping practices and not duplicate
them. It is desirable that the personnel have the opportunity and the ability to chart and tabulate their
own data in order to monitor local trends. In addition the immediate reporting of a disease with
epidemic potential should be followed by an equally immediate response.
WHO Recommended Surveillance Standards
October 97
9
Tasks at the peripheral level:
•
•
•
diagnosis and case management
reporting of cases
simple tabulation and graphing of data
Certain conditions may be subject to community-based surveillance. Community-based
surveillance in this context means the detection and reporting of diseases from within the community
usually by local people or leaders who have received basic instruction on how to recognise certain
conditions. The decision to base surveillance in the community should be based on a clearly identified
needs and advantages over health care unit-based surveillance.
The role of non-govemmental organizations (NGOs) working in the field, including missions’
health facilities, as well as the role of the private sector, have become increasingly important in
disease surveillance. These partners should then be considered in the national surveillance plan
where possible.
The intermediate level is that at which data are collected from the peripheral level. The main
function from the perspective of communicable disease surveillance and control is ongoing analysis of
data from the periphery in order to recognise outbreaks or changes in disease trends. These analyses
should be associated with responses such as investigation and intervention. The effectiveness of
interventions can be monitored using the same data sources.
Countries may have two intermediate levels (e.g. district and region). This will depend on the
size of the country and the structure and level of development of the health service. In many cases the
professional at this level will have other tasks in the area of programme management. Therefore, it is
important that the .tasks be manageable and that the surveillance data be perceived as immediately
useful. In some cases it may be more appropriate that the task of outbreak investigation be undertaken
from the central level.
Tasks at the intermediate level:
• case management which can not be done at the peripheral level
• analysis of data from the peripheral level for
- epidemiological links
- trends
- achievement of control targets
• provision of supportive laboratory data (or laboratory diagnosis if possible)
• investigation of suspected outbreaks
• feedback of information to the peripheral level
• reporting of data and suspected/confirmed outbreaks to central level
The central level is usually at the national level where policies on infectious disease are set
and where resource allocation most often occurs. The central level in some large countries may
actually be at a federal level. The central level plays a key role in supporting the intermediate levels, by
providing services that are not available elsewhere, such as high level epidemiological skills or
laboratory facilities. The central level must also be able to deal with outbreaks of national importance in
a co-ordinated fashion. In addition, overall disease trends can be analysed and resources for disease
control targeted to high-risk areas. The central level must liaise with other countries and international
agencies in the response to outbreaks of international significance and in the management of diseases
subject to the I HR, or to agreed targets for control or elimination. The central level may have access to
alternative data sources such as national reference laboratories where the identification of unusual
organisms should trigger a response.
WHO Recommended Surveillance Standards
October 97
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Tasks at the central level:
•
•
overall support to, and co-ordination of, national surveillance activities
provision of laboratory diagnosis data if not available at intermediate level (use
regional or international reference laboratories if required)
•
analysis of data from intermediate level for:
- epidemiological links
- trends
- achievement of control targets
•
support to intermediate level for outbreak control
- case management
- laboratory
- epidemiology
- education
- logistics
•
•
feedback to intermediate level, and possibly to the peripheral level
report to WHO, as required (International Health Regulations, specific needs of
control programmes)
Collaboration with non-medical sectors such as <agriculture,
’
veterinary medicine, and
environment must be considered where appropriate (e.g. water or food-bome diseases, vector-borne
diseases, human zoonoses).
Zero Reporting-. Whatever the structure of the surveillance system, data on priority diseases
or syndromes should move smoothly through the system triggering the appropriate responses
throughout The system should include zero reporting: each site should report for each • reporting
period even if that means reporting zero cases. This avoids the confusion of equating “no report” with
no cases . In addition the surveillance system must include performance indicators for reporting (e.g.
completeness and timeliness):
Feedback-. It is essential that feedback loops be built iiSto the system. This may be through
regular epidemiological bulletins with tables and graphs showing trends and progress towards targets
and reports on the investigation and control of outbreaks.
WHO Recommended Surveillance Standards
October 97
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Sample Format
Cholera
ICD 10 Code
rzzz
A001
Disease or syndrome
Chol»ra
Case report unrvrully nquifd by international Health Regulations
Rationale for
surveillance
Recommended
case definition
RATIONALE FOR SURVEILLANCE
- --------------- ----- ---------------------------------------Cholera causes an estimation of 120 000 deaths per year and ts prevalent in 80 countnes In Afnca
epidemics have become more frequent and case fatality rates higher. The world is currently expenenong the
7th pandemic. Refugee or displaced populations are at major nsk of ep.oemtcs due to the conditions
prevailing m the camps (unsafe water, poor sanitation and bygone). Control of the disease requ.res
appropnate surveillance with universal case reporting. Health educate of population at nsk ano improvement
or living conditions of population are essential preventrve measures.
RECOMMENDED CASE DEFINITION
--------------------------------------------------- —
Clinical case definition
•
In an area where the d>sease is not known to be present m a patient aged 5 years or more severe
dehydration or death from acute watery diarrhoea or
•
In an area where there is a cholera epidemic, in a patient aged 5 years or more*, acute watery diarrhoea
with or without vomiting.
Laboratory criteria for diagnosis
Isolation of Vibno cMerae 01 or 0139 from stools in any patient with diarrhoea.
Case classification
Suspected.- A case that meets the clinical case definition.
Probtbte: Not applicabie.
Confinnod: A suspected case that ts laboratory-confirmed.
Note: in a choiera-treetened area, when the number of 'confirmed"cases rises, shift should be made to using
pnmanly the 'suspected* case classification.
•Cholera does appear in children under 5 years . however . the inclusion of all cases of acute watery
diarrhoea in the 2-4 year age group tn the reporting of cholera greatly reduces the speofiaty of reporting. For
management of cases of acute watery diarrhoea tn an area where there ts a cholera epidemic, cholera should
be suspected n all patients.
Recommended types
of surveillance
RECOMMENDED TYPES OF SURVEILLANCE
- -------------------------------------------------------------Routine surveillance (This may be integrated with surveillance of diarrhoeal diseases see acute watery
diarrhoea). Immediate case-based reporting of suspected cases from periphery to intermediate level and central level All
suspected cases and dusters should be investigated.
Aggregated data on cases should also be included n routine weekly/morthiy reports from penpheral to
rtermediate and central level
lnt*mationat:
First suspected cases should be reported to WHO (mandatory).
Aggregated data on c^ses should be reported to WHO (mandatory).
Outbreak situatxxis:
•
Dunng outbreak situation surveillance should be intensified with the introduction of active case finding
surveillance.
•
Laboratory confirmation should be performed as soon as possible
•
Thereafter weekly reports of cases, ages, deaths, regions, and hospital admissions should be set up.
Recommended minimum
data elements
Recommended data
analyses, presentation,
reports
Principal uses of data
for decision making
Special aspects
Contact information
RECOMMENDED MINIMUM DATA ELEMENTS
C**«-bas«d data for investigation and reporting
Age, sex. geographical information
Hospitalisation (Y/N)
Outcome
Aggregated data for reporting
Number of cases by age. sex
Number of deaths
RECOMMENDED DATA ANALYSES. PRESENTATION, REPORTS------------------Use weekly numbers, not moving averages
Case fatality rates (graphs)
Weekry/monthty plots by geographical area (district) and age group (GIS) (graphs)
Comparisons with same period m previous five years
PRINCIPAL USES OF DATA FOR DECISION MAKING
Detection of outbreak, estimate the incidence and case fatality rate
Appropriately timed investigations
Assess the spread and progress of the disease
Plan for treatment supplies prevention and control measures
Determine the effectiveness of control measures
SPECIAL ASPECTS
A\ least one reference laboratory m each country ts recommended for speaes identification Once the
presence of coiera m an area has been confirmed . it becomes unnecessary to confirm all subsequent cases.
Monitoring of an epidemic should, however, include laboratory confirmation of a small proponion of cases on
a cont tn u me pasts
CONTACT INFORMATION
'
Regional officas
See Regional Communicable Disease contacts on pages 15-20
Headquarters
WHO Division of Emerging and other communicable Diseases. Surveillance and control (EMC), 20 Avenue
Appia. CH-1211 Geneva 27 Switzerland
E-mail neiram@who.ch / outbreakemc@who cn
Tel (41 22) 791 3977 / 2662 72111
Fax (41 22) 791 4893 / 0746 attn EMC
WHO Recommended Surveillance Standards
October 97
12
Communicable Disease Surveillance Activities by WHO Policy and Division
Selection criteria
Div/Unit
Contact
GPV/EPI
CTD/DRA
H. Hull
Ph. Ranque
LEP
GPV/EPI
GPV/EPI
D. Daumerie
F. Gasse
JM. Oliv£
Targeted for eradication (9GPW6.1)
- poliomyelitis
- dracunculiasis
Targeted for elimination (9GPW 6.2)
- leprosy
- neonatal tetanus
- measles
Targeted for reduced incidence/prevalence (9GPW6.3)
- malaria
- tuberculosis
- hepatitis B
CTD/MAL
GTB
GPV/EPI
A. Rietveld
M. Raviglione
M. Kane
EMC
UNAIDS
M. Anker
B. Schwartlander
Targeted for reduced transmission (9GPW6.4)
- AIDS/HIV
Diseases submitted to International Health Regulations
- yellow fever
- cholera
- plague
EMC
EMC
EMC
R. Arthur
M. Neira
E. Tikhomirov
Other international surveillance/control programmes
- African trypanosomiasis
- brucellosis
- Chagas disease
- CJD & variants
- dengue
CTD/TRY
EMC.
CTD/TRY
EMC
MNH/NRS
EMC
CTD
- diphtheria
- endemic dysenteria
- hepatitis C
- influenza
- leishmaniasis
- leptospirosis
- lymphatic filariasis
- meningococcal meningitis (CSM)
- onchocerciasis
- pertussis (whooping cough)
- rabies
- salmonellosis (animal)
(foodborne)
- schistosomiasis & intestinal parasites
GPV/EPI
EMC
EMC
EMC
CTD/TRY
EMC
CTD/FIL
EMC
AFRO/OCP
GPV/EPI
EMC
EMC
FSF
CTD/SIP
WHO Recommended Surveillance Standards
October 97
P. Cattand
F. Meslin
A. Moncayo
F. Meslin
C. Bolis
R. Arthur
position vacant
(vector surveillance)
B. Melgaard
M. Neira
D. Lavanchy
D. Lavanchy
Ph. Desjeux
F. Meslin
E. Ottesen
E. Tikhomirov
A. Daribi
B. Melgaard
F. Meslin
K. Stbhr
Y. Motarjemi
L. Savioli
13
Surveillance by syndrome or transmission route
- antibiotic resistance
- acute respiratory infections
- diarrhoeal diseases
- food-bo me diseases
- health and demographic data;
causes of death, life table and
mortality trends
- STDs
- other zoonoses
- viral haemorrhagic fevers
EMC
ASD
CHD
CHD
FSF
HST/HSP
E. Tikhomirov
A. Gerbase
D. Robinson
J. Bryce
Y. Motarjemi
O. Frank
ASD
EMC
EMC
A. Gerbase
F. Meslin
R. Arthur
Related and other communicable disease surveillance activities outside WHO/HQ
- cancer registry
- specific regional surveillance
1ARC*
. AFRO
EMRO
EURO
PAHO
SEARO
WPRO
D. Parkin
D. Barakamfitiye
B. Sabrizadeh
S. Dittman
S. Corber
A Andjaparidze
K. Morita
• International Agency for Research on Cancer, 150 Cours Albert Thomas, F-69372 Lyon Cedex 08
Tel. 33 (0) 4 72 73 84 82
Fax. 33(0) 472 73 85 75
E- mail:Parkin@iarc.fr
WHO Recommended Surveillance Standards
October 97
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Communicable Disease Contacts in Regional Offices
1. WHO REGIONAL OFFICE FOR AFRICA (AFRO)
Member states
Algeria
Angola
Benin
Botswana
Burkina Faso
Burundi
Cameroon
Cape Verde
Central African Republic
Chad
Comoros
Congo
Cote d’Ivoire
Democratic Republic of the Congo
Equatorial Guinea
Eritrea
Ethiopia
Gabon
Gambia
Ghana
Guinea
Guinea-Bissau
Kenya
Lesotho
Liberia
Madagascar
Malawi
Mali
Mauritania
Mauritius
Mozambique
Namibia
Niger
Nigeria
Rwanda
Sao Tome and Principe
Senegal
Seychelles
Sierra Leone
South Africa
Swaziland
Togo
Uganda
United Republic of Tanzania
Zambia
Zimbabwe
Contacts
(
Dr D. Barakamfitiye, Director, Prevention and Control of Diseases (DDC), Direct telephone
1 407 953 92 29, fax 1 407 953 9413
Dr A. Ndikuyeze, A/Regional Adviser, Prevention and Control of Diseases (DDC),
Direct telephone: 1 407 953 92 45
E-mail:
AFRO@WHO.ORG
ADIKPETOE@WHO.ORG
BARAKAMFITiYED@HTSD.COM at INET
DALMEIDAA@HTSD.COM at INET
KOUBATIKAK@HTSD.COM at INET
NDIKUEZEA© HTSD.COM at INET
SAMBAE@ HTSD.COM at INET
Note: Following the temporary closure of the AFRO office in Brazzaville, the above contact information
may not be valid. A temporary office is available in Harare
Tel: 263 4 706 951/707 493
Fax: 263 4 705 619/702 044
If you experience any difficulties in communicating with AFRO regarding disease surveillance issues,
please contact EMC at WHO, Geneva, at tel. 41 22 791 21 11 / 2661
Summary of AFRO Regional Plan for communicable disease surveillance (to be provided)
WHO Recommended Surveillance Standards
October 97
15
4. WHO REGIONAL OFFICE FOR EUROPE (EURO)
Member states
Albania
Andorra
Armenia
Austria
Azerbaijan
Belarus
Belgium
Bosnia and Herzegovina
Bulgaria
■Croatia
Czech Republic
Denmark
Estonia
Finland
France
Georgia
Germany
Greece
Hungary
Iceland
Ireland
Israel
Italy
Kazakstan
Kyrgyzstan
Latvia
Lithuania
Luxembourg
Malta
Monaco
Netherlands
Norway
Poland
Portugal
Republic of Moldova
Romania
Russian Federation
San Marino
Slovakia
Slovenia
Spain
Sweden
Switzerland
Tajikistan
The former Yugoslav Republic of
Macedonia
Turkey
Turkmenistan
Ukraine
United Kingdom of
Great Britain and
Northern Ireland
Uzbekistan
• Yugoslavia
Contacts
Professors. F*
Dittman, Coordinator, Communicable Diseases and Immunization and Vaccine
Programme (CDI)
Direct telephone 00 45 39 17 13 98 or 00 45 39 17 14 15 (secretariat)
fax: 00 45 39 17 18 51 E-mail: SDI@WHO;DK
Summary of EURO Regional Plan for communicable disease surveillance (to be provided)
WHO Recommended Surveillance Standards
October 97
18
5. WHO REGIONAL OFFICE FOR SOUTH-EAST ASIA (SEARO)
Member states
Bangladesh
Bhutan
Democratic People’s
Republic of Korea
India
Indonesia
Maldives
Myanmar
Nepal
Sri Lanka
Thailand
Contacts
Acting Director, Integrated Control of Diseases (ICD)
fax: 00 91 11 331 8412
Dr A.G. Andjaparidze, Regional Adviser on Communicable Diseases (CDA)
Direct telephone: 00 91 11 331 7804 to 7823 Fax: 00 91 11 331 8412 E-mail:
ANDJA@WHO.ERNET.IN
Dr Sawat Ramaboot, Regional Epidemiologist, Division of Integrated Communicable Diseases (ICD),
Direct telephone: 00 9111 331-7804 to 00 9111 331-7823
Fax: 00 9111 331-8412 and 00 9111 331-8607
E-mail: SAWAT@WHO.ERNET.IN
Summary of SEARO Regional Plan for communicable disease surveillance
The first priority is to achieve the eradication or elimination of diseases such as dracuncuiiasis (India),
poliomyelitis andjeprosy in the Region.
The second priority is the prevention and control of diseases, which are major public health problems
in the Region, through the establishment of appropriate national and regional surveillance
mechanisms.
The third priority is to undertake short-term and long-term actions to combat newly emerging diseases.
Since speedy response is needed to effectively contain outbreaks, rapid response mechanisms need
to be built into the surveillance system.
The following are regional strategies for the coming few years towards the prevention and control of
communicable diseases:
Strengthening epidemiological surveillance.
Strengthening laboratory capabilities and services
Establishment of rapid response mechanisms
Monitoring antimicrobial resistance
Establishment of international disease surveillance networking
Advocacy and mobilization of international support
WHO Recommended Surveillance Standards
October 97
19
s: WHO REGIONAL OFFICE FOR THE WESTERN PACIFIC (WPRO)
Member states
Australia
Brunei Darussalam
Cambodia
China
Cook Islands
Fiji
Japan
Kiribati
Lao People's Democratic
Republic
Malaysia
Marshall Islands
Micronesia
(Federated States of)
Mongolia
Nauru
New Zealand
Niue
Palau
Papua New Guinea
Philippines
Republic of Korea
Samoa
Singapore
Solomon Islands
Tokelau*
Tonga
Tuvalu
Vanuatu
Viet Nam
* Associate Member
Contacts
Dr Shigeru Omi, Director, Disease Prevention and Control (DPC)
Direct telephone 00 632 522-9961, fax 00632 521-1036 E-mail: OMIS@WHO.ORG.PH
Dr Kouichi Morita, Regional Adviser in Communicable Diseases, CDS(M)
Direct telephone 00 632 522 9964, fax 00 632 521 1036 E-mail: MORITAK@WHO.ORG.PH
Summary of WPRO Regional Plan for communicable disease surveillance
Poliomyelitis surveillance
Surveillance on antimicrobial resistance
STD/AIDS surveillance, including gonococcal infections
- .....
Surveillance on anti-malaria and anti-tuberculosis drug resistance
For other selected infectious diseases, annual or monthly cases are being reported to WPRO.
WPRO is also developing Creutzfeldt-Jacob disease surveillance mechanisms (CJD does not exist at
. present in the Region) as part of global CJD surveillance.
WHO Recommended Surveillance Standards
October 97
20
AIDS
B20-B21-B22-B23-B24
AIDS
(Acquired Immunodeficiency syndrome)
RATIONALE FOR SURVEILLANCE
"
”
------------------------------------AIDS is a disease targeted for reduced incidence, prevalence and transmission (WHO 9GPW, target
6.3). Control measures are based on prevention and care strategies. Surveillance is necessary to
assess national needs in education, supplies, and health care and to anticipate spread in the
community. Surveillance will provide epidemiological data used for national prevention and care plan
and will be essential to evaluate the impact of control activities.
RECOMMENDED CASE DEFINITION
"
------------------------------------ ?---Different case definitions are used in different countries, depending on population factors (children,
adults, relative occurrence of opportunistic infection) and on the laboratory infrastructure and
training available. Current most used case definitions include for countries with
more sophisticated laboratory facilities
limited laboratory facilities
* CDC 1987 (1)
’ CDC/CD4 (2)
* European (3) ■
* Abidjan/WHO (4)
* Bangui/WHO (clinical) (5)
* Caracas/PAHO (6) revised Caracas/PAHO (7)
References:
(
(1) MMWR Aug. 14, 1987/Vol. 36(suppl.)1-15s
(2) MMWR May 2, 1997/Vol. 46/No. RR-10'
(3) Lancet, 1993;341:441 and AIDS Surveillance in Europe, Quarterly Report, 1993 ;number 37
(4) AIDS 1993, Vol. 7 (suppl 1)
(5) AIDS 1993, Vol. 7 (suppl 1)
(6) Epidemiological Bulletin of PAHO Vol. 10 #4 1990
Working group on AIDS case definition pages 9-11
or
Journal of Acquired Immune Deficiency Syndrome Vol. 5 # 12 1992
A simplified surveillance case definition of AIDS derived from empirical clinical data
(7) AIDS 1993, Vol. 7 (suppl 1)
1.1987 CENTERS FOR DISEASE CONTROL AND PREVENTION SURVEILLANCE DEFINITION
FOR AIDS
Without laboratory evidence of HIV infection (in the absence of other causes of immune suppression)
Indicator disease diagnosed definitively
Candidiasis of the oesophagus, trachea, bronchi, or lungs
Cryptococcosis, extrapulmonary
Cryptosporidiosis with diarrhoea persisting > 1 month
Cytomegalovirus diseases of an organ other than liver spleen, or lymph nodes in a patient >1 month of age
Herpes simplex virus infection causing a mucocutaneous ulcer persisting > 1 month; or bronchitis, pneumonitis, or
oesophagitis for any duration in a patient > 1 month of age
Kaposi's sarcoma in a patient < 60 years of age
Lymphoma of the brain(primary) affecting a patient < 60 years of age
Mycobactenum avuim complex or M .kansasii disease, disseminated (at a site other than or in addition to
lungs, skin, or cervical or hilar lymph nodes)
Pneumocystis carinii pneumonia
Progressive multifocal leukoencephalopathy
Toxoplasmosis of the brain in a patient > 1 month of age
WHO Recommended Surveillance Standards
October 97
21
With laboratory evidence of HIV infection
Indicator diseases diagnosed definitively
Coccidiomycosis, disseminated (at a site other than or in addition to lungs or cervical or hilar lymph nodes)
HIV encephalopathy
Histoplasmosis. disseminated(at a sit other than or in addition to lungs or cervical or hilar lymph nodes)
Isosponasis with diarrhoea persisting > 1 month
Kaposi's sarcoma at any age
Lymphoma of the brain (primary ) at any age
Non-Hodgkin’s lymphoma
Any mycobacterial disease caused by mycobacteria other than M. tuberculosis, disseminated
Disease caused by M. tuberculosis, extrapulmonary
Salmonella (non-typhoid ) septicaemia, recurrent
HIV wasting syndrome
Indicator diseases diagnosed presumptively
Candidiasis of the oesophagus
Cytomegalovirus retinitis with loss of vision
Kaposi’s sarcoma
Mycobacterial disease, disseminated
Pneumocystis carinii pneumonia
Toxoplasmosis of the brain in a patient> 1 month of age
2. CONDITIONS* ADDED TO THE CENTERS FOR DISEASE CONTROL AND PREVENTION
WFEC'nON^l'LANCE DEFINITION FOR AIDS (WITH LABORATORY EVIDENCE OF HIV
in addition to those in the 1987 surveillance definition:
•
•
•
•
CD4+ T- lymphocyte count <200 x 10 6 /I (or a CD4 percentage < 14%)
Pulmonary tuberculosis
Cervical cancer, invasive
Recurrent pneumonia (more than one episode within a 12-month period)
3. EUROPEAN AIDS CASE DEFINITION
Same as revised CDC definition without CD4+ T-lymphocyte count
4. REVISED CARACAS AIDS DEFINITION
Symptoms/signs/diagnosis
points assigned
Kaposi’s Sarcoma
Disseminated/extrapulmonary/non-cavitary
pulmonary tuberculosis
10
Oral candidiases/hairy leukoplakia
Pulmonary tuberculosis with cavitation or unspecified
Herpes zoster < 60 years age
Central Nervous System dysfunction
5
5
5
5
Diarrhea a 1 month
Fever(^38*C) £ 1 month
Cachexia or > 10% weight loss
Asthenia > 1 month
Persistent dermatitis
Anaemia, lymphopenia, and/or thrombocytopenia
Persistent cough or any pneumonia (except tuberculosis)
Lymphadenopathy £1 cm at >2 non-linguinal sites
for >1 month
2
2
2
2
2
2
2
10
2
Required point score
a 10
A patient is defined as having AIDS when the cumulative points assigned for manifested conditions equal or exceed the
required score, and HIV serology is positive. “Provisional cases’ are defined when the required point score is achieved but
HIV serology is pending. People with cancer, those receiving immunosuppressive therapies, and those in whom the above
conditions are attributed to underlying conditions other than HIV infection are excluded.
WHO Recommended Surveillance Standards
October 97
22
5. (MODIFIED) ABIDJAN CASE DEFINITION FOR AIDS
Body-weight loss (> 10%) or cachexia, with diarrhoea or both, intermittent or constant, for at least 1 month
not known to be due to a condition unrelated to HIV infection
•
Tuberculosis with the body-weight loss features given above: or disseminated (involving at least two different organs),
miliary or extrapulmonary tuberculosis (which may be diagnosed presumptively)
•
Kaposi’s sarcoma
•
Neurological impairment sufficient to prevent independent daily activities not known to be due to a condition unrelated
to HIV infection (for example, trauma)
Oesophageal candidiasis (which may diagnosed presumptively based on the presence of dysphagia and oral candidiasis)
•
For the purpose of epidemiological surveillance, an adult (>12 years of age) is considered to have AIDS if a tesffor HIV
antibody positive results, and one or more of the above are present.
6. BANGUl/WHO/CLINICAL
WHO clinical case definition for AIDS in adults when diagnostic resources are limited:
AIDS in an adult is defined by the existence of at least two major symptoms/signs and at least one minor symptom/sign in
the absence of known causes of immunosuppression (e.g. cancer, malnutrition). The presence of generalised Kaposi
sarcoma or cryptococcal meningitis is sufficient by itself for the diagnosis of AIDS.
Major signs:
.
more than 10% weight loss
chronic diarrhoea (for more than 1 month)
.
prolonged fever (intermittent or constant, for more than 1 month)
Minor signs:
. persistent cough (for more than 1 month)
.
generalised pruritic dermatitis
.
recurrent herpes zoster
.
oropharyngeal candidiasis
.
chronic progressive and disseminated herpes virus infection
. generalised lymphadenopathy
Contact Regional/ National AIDS programmes for case definition in use in a specific country.
Case classification
Depends on the case definition
Please check with National AIDS programmes.
RECOMMENDED TYPES OF SURVEILLANCE
—
Routine monthly reporting of aggregated data from periphery to intermediate level.
Routine quarterly reporting of aggregated data from intermediate level to central level.
Sentinel surveillance could be used when routine national surveillance is not possible.
International: report updates every 6 months in WHO
Other sources of data:
• Hospital
• Dermatologist
• STD clinics
• Tuberculosis wards
• Mortality reports and statistics
• Active case finding
WHO Recommended Surveillance Standards
October 97
23
RECOMMENDED MINIMUM DATA ELEMENTS
Case-based data for reporting
Unique identifier, age, sex, geographical area, risk factors (e.g. blood transfusion, drug use,
multiple sexual partners)
Aggregated data for reporting
Number of cases by age and sex, number of cases by risk factors (e.g. blood transfusion, drug
use, multiple sexual partners)
RECOMMENDED DATA ANALYSES, PRESENTATION, REPORTS
Graphs: Number of cases by age, sex, geographical area, risk factors
Tables: Number of cases by age, sex, geographical area, risk factors
Maps: Number of cases by geographical area
PRINCIPAL USES OF DATA FOR DECISION MAKING
• Assess the magnitude of the problem
• Identify high risk areas for further intervention
• Evaluate impact of intervention
• Plan public health measurements
• Assess impact on clinical services
• Plan health care services and supplies
SPECIAL ASPECTS
Use of HIV surveillance (see page 51) for forecasting AIDS incidence
CONTACT
Regional offices
See Regional Communicable Disease contacts on pages 15-20
Headquarters
UNA1DS/WH0 Technical Working Group on Global HIV/AIDS and STD Surveillance
WHO, 20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: surveillance@unaids.org
Tel: (41 22) 791 2380/4551
Fax: (41 22) 791 4198
WHO Recommended Surveillance Standards
October 97
24
Anthrax
A22
Anthrax
(human)
RATIONALE FOR SURVEILLANCE
- ------- ---------------------------- t-------------Anthrax is a widespread zoonosis transmitted from domestic animals (cattle, sheep, goats,
buffaloes, pigs and other) to humans by direct contact or through animal products. Human'anthrax is
a serious problem in several countries and it has potential for explosive outbreaks especially of
intestinal form. Anthrax has a serious impact on trade of animal products. The control of anthrax is
based on prevention. There is an effective human vaccine. Surveillance is important to monitor the
control programmes and to detect outbreaks. In most countries anthrax is a notifiable disease.
RECOMMENDED CASE DEFINITION
----- ---Clinical description
An illness with acute onset characterised by several clinical forms. These are:
(a) localised form:
• cutaneous: skin lesion evolving over 1 to 6 days from a papular through a
vesicular stage, to a depressed black eschar invariably accompanied by
oedema that may be mild to extensive.
(b) systemic forms:
• intestinal, abdominal distress characterised by nausea, vomiting, anorexia and
followed by fever
• inhalation: brief prodrome resembling acute viral respiratory illness, followed
by rapid onset of hypoxia, dyspnea and high temperature, with X-ray evidence
of mediastinal widening
• meningeal: acute onset of high fever possibly with convulsions and loss of
consciousness, meningeal signs and symptoms
Laboratory criteria for diagnosis
Laboratory confirmation by one or more of the following:
• Isolation of Bacillus anthracis from a clinical specimen (e.g. blood, lesions, discharges)
• Demonstration of B. anthracis in a clinical specimen by microscopic examination of stained
smears of vesicular fluid, blood, cerebrospinal fluid, pleural fluid, stools, etc.
• Positive serology (ELISA, Western blot, toxin detection, chromatographic assay, fluorescent
antibody test (FAT), PCR)
Note: It may be not possible to demonstrate B. anthracis in clinical specimens if the patient has
been treated with antimicrobial agents.
Case classification
Suspected:
A case that is compatible with the clinical description and has an epidemiological
link to confirmed or suspected animal cases or contaminated animal products
Probable
A suspected case that has a positive reaction to allergic skin test (in non
vaccinated individuals)
Confirmed:
A suspected case that is laboratory-confirmed
RECOMMENDED TYPES OF SURVEILLANCE
Routine surveillance, particularly among high risk groups (e.g., abattoir workers, shepherds,
veterinarians).
Mandatory immediate case-based reporting by peripheral level (health care providers or laboratory)
to upper level of the public health sector as well as to the appropriate level of the animal health
sector. All cases must be investigated.
Routine monthly reporting of aggregated data of confirmed cases and investigation reports from
intermediate level to central level.
WHO Recommended Surveillance Standards
October 97
25
RECOMMENDED MINIMUM DATA ELEMENTS
"
"—
Case-based data for investigation and reporting:
Case classification by type (suspected/probable/confirmed), and by clinical form
(cutaneous/intestinal/inhalation/meningeal)
Unique identifier, age, sex, geographical information, occupation
Date of onset, date of reporting
Exposure history
Outcome
Aggregated data for reporting to central level.
Number of confirmed cases by age, sex, clinical form
(cutaneous/intestinal/inhaiation/meningeal)
RECOMMENDED DATA ANALYSES, PRESENTATION, REPORTS
"
Graphs: Number of suspected/probable/confirmed cases by date
Tables: Number of suspected/probable/confirmed cases by date, age, sex, geographical area
Maps: Number of human cases by geographical area
PRINCIPAL USES OF DATA FOR DECISION MAKING
Surveillance data
• Estimate the magnitude of the problem
• Monitor the distribution and the spread of human disease
• Detect outbreaks
• Monitor and evaluate impact of prevention activities in humans
Investigation data
• Identify populations at risk
• Identify potentially contaminated products of animal origin
SPECIAL ASPECTS
T
--- ------------------------------------------ --------------The surveillance activities of both public health and animal health sector must be fully co-ordinated
and integrated. Administrative arrangements between the two sectors must be established to
facilitate immediate cross notification of cases/outbreaks, as well as joint case/outbreak
investigations.
CONTACT
Regional offices
See Regional Communicable Disease contacts on pages 15-20
Headquarters
WHO Division of Emerging and other Communicable Diseases, Surveillance and Control (EMC),
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: cosivio@who.ch/ outbreakemcgwho ch
Tel: (41 22) 791 2531 /4687/2111
Fax: (41 22) 791 4893 / 0746 attn EMC
WHO Recommended Surveillance Standards
October 97
26
Bacillary dysentery
AOS
Bacillary dysentery
(caused by Shigella dysenteriae type 1)
RATIONALE FOR SURVEILLANCE
“
Since the early 1990’s the emergence of strains of Shigella dysenteriae type 1, resistant to most
antibiotics, has become a major public health concern in central and southern Africa. The high case
fatality and the epidemic potential make surveillance to detect and control the outbreaks essential.
RECOMMENDED CASE DEFINITION
Clinical case definition
Diarrhoea with visible blood in the stool
Laboratory criteria for diagnosis
Isolation of S. dysenteriae type 1 from stools
Case classification
Suspected:
A case that meets the clinical case definition
Probable:
Not applicable
Confirmed:
A suspected case that is laboratory-confirmed
RECOMMENDED TYPES OF SURVEILLANCE
"
------ ------ ---------Routine weekly/monthly reporting of aggregated data on suspected cases from periphery to
intermediate level (This may f)e integrated with surveillance of diarroeal diseases).
Routine weekly/monthly reporting of data on confirmed cases from intermediate level to central
level.
Note:
• Intensified surveillance if suspected outbreak: immediate reporting to central level and WHO
regional office and investigation
• Central recording of antibiotic resistance is recommended 1
RECOMMENDED MINIMUM DATA SET
- ----------------------------------Case-based data for reporting and investigation
Case classification (suspected/confirmed), unique identifier, age, geographical information
Treatment given(YZN), kind of treatment
Outcome
Aggregated data for reporting
Number of cases (suspected/confirmed) by age group (under or over 5 years), number of
hospitalisations, number of deaths
WHO Recommended Surveillance Standards
October 97
27
RECOMMENDED DATA ANALYSES, PRESENTATION, REPORTS
• Comparisons with same period in previous years
• Case fatality rates, age specific incidence rates (under or over 5 years)
•
Plots of laboratory-confirmed cases by month and year
• Quarterly or annual central overview
During outbreaks
• Weekly/monthly plots by intermediate level
• Monthly surveillance summaries should be produced centrally and at WHO regional office with
feedback
PRINCIPAL USES OF DATA FOR DECISION MAKING
-------------------• Detect and monitor outbreaks and epidemics for appropriate response
• Estimate incidence, and case fatality rate
• Support plan for the distribution of medical supplies (diagnostic test, antibiotics etc.) and
allocation of control teams
• Determine the effectiveness of control measures
• Provide research data in the area of means of transmission and antibiotic susceptibility of
isolates (monitor antimicrobial resistance)
• Help mobilising donors to support epidemic control measures
SPECIAL ASPECTS
Countries at risk from epidemics should have routine surveillance of bloody diarrhoea. This is
particularly recommended for countries of central and southern Africa.
Each country should have at least 1 reference laboratory in order to confirm the
organism/outbreak, perform antimicrobial susceptibility testing, perform training and disseminate
results.
At least 20 specimens should be collected to confirm the cause of the outbreak. Patients for culture
should have bloody diarrhoea for less than 4 days, without treatment Rectal swabs or swabs of
stool passed within an hour should be placed in Cary Blair media and transported cold (refrigerated
or frozen). Culture should be on Mac-Conkey XLD media.
CONTACT INFORMATION
Regional offices
See Regional Communicable Disease contacts on pages 15-20
Headquarters
WHO Division of Emerging and other Communicable Diseases Surveillance and Control (EMC)
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: neiram@who.ch / outbreakemc@who.ch
Tel: (41 22) 791 3977 / 2662 /2111
Fax: (41 22) 791 48 93 / 07 46 attn EMC
WHO Recommended Surveillance Standards
October 97
28
Brucellosis
A23
Brucellosis
(human)
RATIONALE FOR SURVEILLANCE
- ------------------------------------ ------------Brucellosis is the most widespread zoonosis transmitted from animals (cattle sheep goats pios
camels and buffaloes) by direct contact with blood, placenta, fetuses or uterine secretions or
through consumption of infected and raw animal products (especially milk and milk products)
Human brucellosis due to Brucella melitensis has serious public health consequences in areas
where sheep and goat are raised. Overall brucellosis has an important world-wide impact on human
health and the animal industry. In most countries Brucellosis is a notifiable disease Control
measures are based on prevention. Surveillance is a key element for management of prevention
and control programmes.
K
RECOMMENDED CASE DEFINITION
---------------Clinical description:
An illness characterised by acute or insidious onset, continued, intermittent or irregular fever of
vanab e duration, profuse sweating particularly at night, fatigue, anorexia, weight loss, headache,
arthralgia and generalised aching. Local infection of organs may occur.
Laboratory criteria for diagnosis
. Isolation of Brucella spp. from clinical specimen or
. Brucella agglutination titre e.g. standard tube agglutination tests: SAT>= 160 in one or more
serum specimens obtained after onset of symptoms or
‘ EL!kAJI9(A’ l^' l9M)' 2^ercaPtoethanol test, complement fixation test, Coombs, fluorescent
an i o y test (FAT), and radioimmunoassay for detecting antilipopolysaccharde antibodies' and
countenmmunoelectrophoresis (CIEP) for antibodies anticytosoiic proteins
Case classification
Suspected:
A case that is compatible with the clinical description and is
epidemiologically linked to suspected or confirmed animal cases or
contaminated animal products
Probable:
A suspected case that has a positive Rose Bengale test
Confirmed:
A suspected orprobable case that is laboratory-confirmed
\
RECOMMENDED TYPES OF SURVEILLANCE
- -------------------------Routine surveillance, particularly among high risk groups (farmers, shepherds, workers in
slaughterhouses, butchers, veterinarians, laboratory personnel)
Mandatory 'mrnedi3^ case-based reporting by health care providers or laboratory to upper level of
the public health sector as well as to the appropriate level of the animal health sector. In endemic
countnes if case-based reporting is not feasible: immediate outbreak reporting
All cases/outbreaks should be investigated.
WHO Recommended Surveillance Standards
October 97
29
RECUMMbNUtD MINIMUM DATA ELEMENTS------ ----- -------Case-based data for investigation and reporting
Case classification (suspected/probable/confirmed)
Exposure history
Outcome
Outbreak data
XSX to“X:S'a"On
a,e. sex. 9sograptol
Aggregated data
Number of cases by case classification (probable/confirmed), age, sex, geographies, area,
occupation
--------------------
ȣ s;::
PRINCIPAL USES OF DATA FOR DECISION MAKING--------------------------------------------------------Surveillance data
’ .E.Sti >atttheJma9nitUde Of the Problem in humans and animals
• Mentor the distribution of the disease in humans and an.maS
Detect outbreaks in humans and animals
Mentor .nd er.luate imp?ct oi prevenBo„ acMt|es
|n
Investigation data
• Identify populations at risk
’ ih!0^ p°tential|y contaminated products of animal origin.
dentify potentially infected animal sources (herds or flocks)
SPECIAL ASPECTS
tod'
--- -- ---------- ----------------------------- ----------- - --------------------------------- a";™'
™*> be fully e„rdlna,ed
facilitate immediate cross notificSon nfXe b, t*®en ‘he
sectors must be established to
investigations.
nobfication of cases/outbreaks, as well as joint case/outbreak
Surveillance and control programmes must be promoted in goat raising areas.
CONTACT INFORMATION---------- ---------------------------------------------- - ------------------------------------Regional offices
See Regional Communicable Disease contacts on pages 15-20
Headquarters
WHO Division of Emerging and other Communicable
20 Avenue Appia, CH-1211 Geneva 27, Switzerland Diseases Surveillance and Control (EMC),
E-mail: cosiv.o@who.ch / outbreakemc@who ch
Tel: (41 22) 791 2531 /4687/2111
Fax: (41 22) 791 48 93 / 07 46 attn EMC
WHO Recommended Surveillance Standards
October 97
30
Cholera
A 00
Cholera
Case report universally required by International Health Regulations
RATIONALE for surveillance
Cholera causes an estimation of 120 000 deaths per year and is prevalent in 80 countries. In Africa
epidemics have become more frequent and case fatality rates higher. The world is currently
experiencing the 7th pandemic. Refugee or displaced populations are at major risk of epidemics due
to the conditions prevailing in the camps (unsafe water, poor sanitation and hygiene). Control of the
disease requires appropriate surveillance with universal case reporting. Health education of
population at risk and improvement of living conditions of population are essential preventive
measures.
RECOMMENDED CASE DEFINITION
Clinical case definition
• In an area where the disease is not known to be present, severe dehydration or death from acute
watery diarrhoea in a patient aged 5 years or more or
• In an area where there is a cholera epidemic, acute watery diarrhoea, with or without vomiting in
a patient aged 5 years or more*
Laboratory criteria for diagnosis
Isolation of Vibrio cholerae 01 or 0139 from stools in any patient with diarrhoea
Case classification
A case that meets the clinical case definition
Suspected:
Not applicable
Probable:
A suspected case that is laboratory-confirmed
Confirmed:
Note: in a cholera-threatened area, when the number of “confirmed" cases rises, shift should be
made to using primarily the “suspected “case classification.
*Cholera does appear in children under 5 years, however, the inclusion of all cases of acute watery
diarrhoea in the 2-4 year age group in the reporting of cholera greatly reduces the specificity of
reporting. For management of cases of acute watery diarrhoea in an area where there is a cholera
epidemic, cholera should be suspected in all patients.
RECOMMENDED TYPES OF SURVEILLANCE
Routine surveillance (this may be integrated with surveillance of diarrhoeal diseases: see acute
watery diarrhoea).
Immediate case-based reporting of suspected cases from periphery to intermediate level and central
level. All suspected cases and clusters should be investigated.
Aggregated data on cases should also be included in routine weekly/monthly reports from peripheral
to intermediate and central level.
International:
The initial suspected cases should be reported to WHO (mandatory)
Aggregated data on cases should be reported to WHO (mandatory).
Outbreak situations:
• During outbreak situations surveillance should be intensified with the introduction of active case
finding
• Laboratory confirmation should be performed as soon as possible
• Thereafter weekly reports of cases, ages, deaths, regions, and hospital admissions should be set
up
WHO Recommended Surveillance Standards
October 97
31
RECOMMENDED MINIMUM DATA ELEMENTS
Case-based data for investigation and reporting
Age, sex, geographical information
Hospitalisation (Y/N)
Outcome
Aggregated data for reporting
Number of cases by age, sex
Number of deaths
RECOMMENDED DATA ANALYSES, PRESENTATION, REPORTS
• Use weekly numbers, not moving averages
• Case fatality rates (graphs)
.• Weekly/monthly plots by geographical
.
1 area (district) and age group (GIS) (graphs)
• Comparisons with same period in previous five years
Principal uses of data for decision making
• Detect outbreaks, estimate the incidence and case fatality rate
• Appropriately timed investigations
• Assess the spread and progress of the disease
• Plan for treatment supplies prevention and control measures
• Determine the effectiveness of control measures
Special Aspects
-- ------:------------------------------------------At least one reference laboratory in each country is recommended for species identification
Once the presence of cholera in an area has been confirmed, it becomes unnecessary to confirm all
subsequent cases. Momtonng of an epidemic should, however, include laboratory confirmation of a
small proportion of cases on a continuing basis.
CONTACT INFORMATION
?— ----------- —---------------- -----------------------------Regional offices
See Regional Communicable Disease contacts on pages 15-20
Headquarters
WHO Division of Emerging and other Communicable Diseases Surveillance and Control (EMC)
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail, neiram@who.ch / outbreakemc@who ch
Tel: (41 22) 791 3977 / 2662 72111
Fax: (41 22) 791 4893 / 0746 attn EMC
WHO Recommended Surveillance Standards
October 97
32
Creutzfeldt-Jakob Disease
A81.0
Creutzfeldt-Jakob Disease
(CJD)
RATIONALE FOR SURVEILLANCE:
The incidence of CJD and its variants is currently not monitored in many parts of the world.
In 1996 a new variant of CJD(nvCJD) was recognised in the United Kingdom. An etiological link
between nvCJD and the agent of bovine spongiform encephalopathy (BSE) was considered likely,
leading to great public concern. Subsequently scientific evidence supporting a link has become
available. The size of the population exposed and susceptible to this agent in the United Kingdom is
not known and, in addition to uncertainties relating to the potential length and distribution of the
incubation period, make a useful prediction of the future number of nvCJD cases difficult Other
populations may have also been exposed to the agent through importation of live cattle or cattle by
products from BSE-affected countries, or through the use of medicinal or cosmetic products
containing bovine tissues. Global surveillance of the new variant and other forms of CJD are likely to
lead to greater understanding of these diseases, including the potential causes of iatrogenic CJD
and the distribution of the various hereditary forms, and will provide information towards protection
against the risks of disease.
RECOMMENDED CASE .DEFINITION of CJD subtypes
1. Sporadic CJD
a. Suspected (possible) CJD:
• Progressive dementia; and
• EEG atypical or not known; and
• Duration < 2 years; and
At least two out of the following four clinical features: Myoclonus, visual or cerebellar
disturbance, pyramids;- 'trapyramidal dysfunction, akinetic mutism
b. Probable CJD:
• Progressive dementia; and
• Typical EEG (1-2 Hz generalised repetitive bi/triphasic periodic complexes); and
• At least two out of the following four clinical features: Myoclonus.visual or cerebellar
disturbance, pyramidal/extrapyramidal dysfunction, akinetic mutism
a. Confirmed (definite) CJD:
• Anatomopathologically confirmation; and/or
• Immunocytochemically confirmed prion protein (PrP) positive (Western blot); and /or
•
Presence of scrapie associated fibrils
2. Iatrogenic CJD
• Progressive cerebellar syndrome in a recipient of human cadaver-derived pituitary
hormone; or
• Sporadic CJD with a recognised exposure risk
3. Familial CJD
Note:
For the purpose of surveillance this includes Gerstmann-StrSussler-Scheinker
syndrome (GSS) and fatal familial insomnia (FFI)
• Confirmed or probable CJD plus confirmed or probable CJD in a first degree relative
and/or
• neuropsychiatric disorder plus disease-specific PrP mutation
4. New variant CJD
Neuropathology is mandatory for the diagnosis of definite nvCJD:
• Abundant kuru-like amyloid plaques surrounded by vacuoles (clearly visible on H&E and
PAS stains);
• Abundant PrP deposits on immunocytochemistry, including prominent ‘pericellular’
WHO Recommended Surveillance Standards
October 97
33
•
'
Marked thalamic astrocytosis;
are characteristic of nvCJD, although not sufficient for a definite
probable or possible case are not yet available,
y
• A psychiatric presentation with depression and/or psychosis lasting weeks or months
• Onset of progressive unsteadiness within weeks or months of presentation
• Early and persistent paraesthaesia/ dysaesthesia
• Chorea and/or myoclonus
’ sigtns'llr,eSS Pr09reSSi°n Sirnilar t0 classical CJD’ with dementia and multifocal neurological
•
•
EEG does not show 'typical' appearance and may be normal
images30 Sh°WS POSteriOr thalarnic h'9h signal on T2-and/or proton density-weighted
• Prolonged duration
• Young age
Genetic analysis to exclude familial CJD is important and patients should have no history of
exposure to a known risk factor for iatrogenic disease.
RECOMMENDED TYPES OF SURVEILLANCE
----------------------------------One centre should be identified at central level to carry out surveillance
All reporting should be case- based
All definite, probable and possible cases should be notified by the appropriate health care
professionals (usually physicjans, neurologists, psychiatrists or neuropathologists) to the centre
responsible for surveillance.
Note: Death notification surveillance. Death registrations should be checked in order to identify
cases not detected by routine surveillance.
RECOMMENDED MINIMUM DATA ELEMENTS
Case-based data for reporting:
Subtype and classification of CJD
*
Age, sex, country of birth, geographical information, occupation
Date of onset, date of death
Vital status (alive, dead) "
RECOMMENDED DATA ANALYSES, PRESENTATION, REPORTS-----------------------------Number of cases by subtype, by classification, by occupational group, by geographical area
Number of cases by year of death, by age at death
Sex ratio
Principal uses of data for decision making
• To plot the trend in incidence of CJD subtypes
• To detect clusters of cases requiring further investigation
• To identify risk factors for disease acquisition
Special aspects
"
- --------- —
None
CONTACT
--- ------------------------------------------Regional offices
See Regional Communicable Disease contacts on pages 15-20
Headquarters
WHO Division of Emerging and other communicable Diseases, Surveillance and control (EMC)
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: meslinf@who.ch / outbreakemc@who.ch
[Tel: (41 22)791 2575 /4687/2111 Fax: (41 22) 791 4893 / 0746 attn EMC______________
WHO Recommended Surveillance Standards
October 97
34
Dengue
A90, A91
Dengue Fever (A90/ including Dengue Haemorrhagic Fever and
Dengue Shock Syndrome (DHF & DSS, A91)
RATIONALE FOR SURVEILLANCE
Dengue fever, including DHF and DSS, is the most significant arthropod-borne viral disease world
wide. It occurs in over 100 countries and territories and threatens the health of over 2 500 million
people in tropical and subtropical regions. Dengue fever is a severe disease with high epidemic
potential. An estimated 500 000 patients are hospitalised with DHF/DSS every year, 90% of whom
under the age of 15. WHO aims to accelerate the final development of attenuated dengue vaccine.
RECOMMENDED CASE DEFINITION
DENGUE FEVER
Clinical description
An acute febrile illness of 2-7 days duration with two or more of the following manifestations:
headache, retro-orbital pain, myalgia, arthralgia, rash, haemorrhagic manifestations, leucopenia
Laboratory criteria for diagnosis
one or more of the following:
• Isolation of the dengue virus from serum, plasma, leukocytes, or autopsy samples
• Demonstration of a fourfold or greater change in reciprocal IgG or IgM antibody titres to one or
more dengue virus antigens in paired serum samples
• Demonstration of dengue virus antigen in autopsy tissue by immunohistochemistry or
immunofluorescence or in serum samples by EIA
• Detection of viral genomic sequences in autopsy tissue, serum or CSF samples by polymerase
chain reaction(PCR)
Case classification
A case compatible with the clinical description
Suspected:
A case compatible with the clinical description with one or more of the following:
Probable:
• supportive serology (reciprocal haemagglutination-inhibition antibody titre >
1280, comparable IgG EIA titre or positive IgM antibody test in late acute or
convalescent-phase serum specimen)
• occurrence at same location and time as other confirmed cases of dengue fever
A case compatible with the clinical description that is laboratory-confirmed
Confirmed:
CRITERIA FOR DENGUE HAEMORRHAGIC FEVER AND DENGUE SHOCK SYNDROME
Dengue Haemorrhagic Fever:
A probable or confirmed case of Dengue
and haemorraghic tendencies evidenced by one or more of the following
• positive tourniquet test
• petechiae, ecchymoses or purpura
• bleeding from mucosa, gastrointestinal tract, injection sites or other sites
• haematemesis or melena
and thrombocytopenia (100 000 cells per mm3 or less)
and evidence of plasma leakage due to increased vascular permeability, manifested
by one or more one of the following:
• a rise in average haematocrit for age and sex > 20%
• a > 20% drop in haematocrit following volume replacement treatment compared
to baseline
• signs of plasma leakage (pleural effusion, ascites hypoproteinaemia)
WHO Recommended Surveillance Standards
October 97
35
Dengue shock syndrome.
------------------------------- --------------------------------All the above enter,a for DHF plus evidence of circulatory failure manifested bv
manifested by
rapid and weak pulse, and narrow pulse pressure (<20 mm Hg)
hypotension for age, and cold, clammy skin and restlessness
RECOMMENDED TYPES OF SURVEILLANCE
’— -----------------------------—
Areas where no dengue transmission has been detected but where Aedes aeqvDti occurs
Surveillance o, suepeaec cases
investigation of clusters of suspectec X“s Sdengue
S’“Ona' "”r“S“
•»»
RECOMMENDED MINIMUM DATA ELEMENTS
"
Case-based data at the peripheral level
Case classification (suspected/probable/confirmed), serotype, DHF/DSS present (Y/N)
Date o" onset
9eo9raphicaHnformation
’
Hospitalised (Y/N)
Outcome
2 week travel history
Aggregated data for reporting
Number of cases by age group
Number of confirmed (and serotype)
Number of DHF/DSS cases by age group
Number of hospitalisations and deaths
RECOMMENDED DATA ANALYSES, PRESENTATION
REPORTS
Percentage of DHF/DSS cases and of hospitalisations
Case fatality
PRINCIPAL USES OF DATA FOR DECISION MAKING
• Target high risk areas for intervention
• Monitor changes in serotype and rate of DHF/DSS
Monitor trends in endemic disease or re-emergence of disease
SPECIAL ASPECTS
______ _ _____________________________
Parallel to d.sease surveillance, vector surveillance of both larval and adult populations of A aegypti
“CONTACT
---------- --------------------------------------------------------------------------------------Regional offices
See Regional Communicable Disease contacts on pages 15-20
Headquarters
^^e^ueApp^a^QH-T^T^Geneva^^S^^erl^nd 6 01563565 SUrVei"ance and Control <EMC>
E-mail: arthurr@who.ch / outbreakemc@who ch
Tel: (41 22) 791 2658 / 2850 / 2111
Fax:(41 22)791 4878
WHO Recommended Surveillance Standards
October 97
36
Diphtheria
A36
Diphtheria
RATIONALE FOR SURVEILLANCE
Diphtheria is a widespread severe infectious disease that has the potential for epidemics.
The control of diphtheria is based on the following three measures 1) primary prevention of disease
by ensuring high population immunity through immunization; 2) secondary prevention of spread by
the rapid investigation of close contacts, to ensure their proper treatment, 3) tertiary prevention of
complications and deaths by early diagnosis and proper management. Surveillance data can be
used to monitor levels of immunization coverage (Target > 90%) and disease, to predict epidemics
and to monitor the impact of control programmes. Recent epidemics have highlighted the need for
adequate surveillance and epidemic preparedness.
RECOMMENDED CASE DEFINITION
Clinical case definition
An illness characterised by laryngitis or pharyngitis or tonsillitis, and
an adherent membrane of the tonsils, pharynx and/or nose
Laboratory criteria for diagnosis
• isolation of Corynebacterium diphtheriae from a clinical specimen, or
• fourfold or greater rise in serum antibody, (but only if both serum samples were obtained before
the administration of diphtheria toxoid or antitoxin)
Case classification
Not applicable
Suspected:
A case that meets the clinical description
Probable:
A probable case that is laboratory-confirmed or linked epidemiologically to a
Confirmed:
laboratory-confirmed case
y
Note: Asymptomatic persons with positive C. diphthenae cultures (i.e. asymptomatic carriers)
should not be reported as probable or confirmed diphtheria cases *
RECOMMENDED TYPES OF SURVEILLANCE
Routine monthly reporting of aggregated data of probable or confirmed cases from peripheral level
to intermediate and central level.
All outbreaks should be investigated immediately and case-based data collected.
In addition in countries achieving low incidence (usually where coverage is >85-90%): immediate
reporting of case-based data of probable or confirmed cases from peripheral level to intermediate
and central level.
International:
Aggregated data of probable or confirmed cases from national reports should
be reported monthly to the WHO regional offices.
RECOMMENDED MINIMUM DATA ELEMENTS
Aggregated data for reporting:
• Number of cases
• DTP doses administered to infants
Case-based data
• Unique identifier
• Geographical information
• Date of birth
• Date of onset
• Date of first treatment
• Treatment type (antibiotic & antitoxin/antibiotic only/antitoxin only/no or other treatment/unknown)
WHO Recommended Surveillance Standards
October 97
J'
ba^atOry result (toxi9enic C. diphtheriae isolated/ non-toxigenic C. diphtheriae isolated /C.
/unknown)6 IS°*ate^' tox’9en’city unknown/C. diphtheriae not isolated /no specimen processed
•
•
•
•
Total diphtheria vaccine (DPT, DT or Td) doses received
Date of last dose
Final classification of the case (confirmed by lab or epi-link/clinical /no lab or epi-link/discarded)
Outcome(alive/dead /unknown)
RECOMMENDED DATA ANALYSES, PRESENTATION, REPORTS
Aggregate data:
Incidence rate by month, year, and geographic area
DTPS coverage by year and geographic area
Completeness/timeliness of monthly reporting
Proportional morbidity (compared to other diseases of public health importance)
Case-based data: same as aggregate data plus the following:
Age-specific incidence rate
Cases by immunization status, laboratory results, treatment type
Cases treated "on time" (< 7 days of onset)
Case fatality rate
Proportional mortality (compared to other diseases of public health importance)
SPECIAL ASPECTS
---------------- -------------------------More detailed information (e.g.coding) available at EPI
PRINCIPAL USES OF DATA FOR DECISION-MAKING
"
• Monitor case fatality rate, and if high, determine cause (e.g. poor case management, lack of
antibiotics/anti-toxin, patients not seeking treatment in time) so that corrective action can be
taken
t
• Determine age-specific incidence rate, geographical area, and season of diphtheria of cases to
know nsk groups and risk period
• Monitor incidence rate to assess impact of control efforts
• Monitor immunization coverage per geographical area to identify areas of poor programme
performance
• Detect outbreaks and implement control measures
• Investigate outbreaks to understand epidemiology, determine why the outbreak occurred (e.g.
vaccine failure, failure to immunise, accumulation of susceptibles, waning immunity, new
toxigenic strain), and ensure proper case management
Note:
In addition to surveillance, carefully designed serological studies can be used to monitor the
immune status of different age groups
CONTACT INFORMATION
Regional offices
See Regional Communicable Disease contacts on pages 15-20
Headquarters
WHO Global Programme for Vaccines and Immunization (GPV)
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: melgaardb@who.ch / gpv@who.ch
Tel: (41 22) 791 4408/4410/2111
Fax: (41 22) 791 0746 attn GPV
WHO Recommended Surveillance Standards
October 97
38
Dracunculiasis
B72
Dracunculiasis
(Guineaworm disease)
RATIONALE FOR SURVEILLANCE
Dracunculiasis is the subject of a global eradication programme (9GPW, target 6.1). Surveillance
is therefore essential to identify and contain all individual cases in endemic countries as well as in
countries where environmental conditions are appropriate for local transmission of the disease.
RECOMMENDED CASE DEFINITION
Clinical case definition
A case of dracunculiasis is defined as an individual exhibiting or having a history of a skin lesion
with the emergence of a Guinea worm. A recent history (within one year) of a skin lesion with
emergence of a Guinea worm is the only time-frame which must be used in surveillance
programmes.
RECOMMENDED TYPES OF SURVEILLANCE
peripheral level: in all endemic and formerly endemic countries, village-based surveillance aims
to detect cases while the worm is pre-emergent or at latest 24 hours after the beginning of
worm emergence, even in the most remote local villages. Community-oriented case
containment interventions are being combined with surveillance to interrupt further
transmission of the disease. For lack of previously trained health workers in highly remote
localities and needs of health workers in newly identified endemic villages, training continues
to be an important activity.
Intermediate /central level: Reports (aggregated data) are gathered from all villages to
intermediate level and channelled towards the central level on a monthly basis. This is
generally combined with supervision activities at all levels of the national dracunculiasis
eradication programmes. When the annual incidence is close to zero, cases should be
reported on a weekly or even daily basis.
>
International level: Reports from endemic countries are aggregated and reported to the
international level on a monthly basis, and used as the basis for policy and managerial
decisions by the central programmes, as well as by the external supporting agencies.
RECOMMENDED MINIMUM DATA ELEMENTS
Case-based data:
Unique identifier, sex, age, geographical co-ordinates of the village involved, date of diagnosis,
case isolation measures taken
Aggregated data:
For every village, number of cases by month and year
RECOMMENDED DATA ANALYSIS, PRESENTATION, REPORTS
Monthly and yearly incidences by village, geographic origin of imported cases. Analysis of the
monthly and yearly changes in the distribution of infected villages. Mapping of data including the
matching of endemic villages with water distribution data, using GIS software.
PRINCIPAL USES OF DATA FOR DECISION MAKING:
• Plan interventions and supervision at all levels of the programme
• Monitor progress and the need for resources of various types
• Identify variations in case-containment efficacy
• Identify technical and operational difficulties at all levels
• Identify areas needing special interventions, training and supervision
• Evaluate the impact of programme activities
WHO Recommended Surveillance Standards
October 97
39
SPECIAL ASPECTS
--------------------------------------------------Rewards are increasingly being added, to enhance central dracunculiasis surveillance systems as
the number of cases continues to decrease. Rewards increase the surveillance sensitivity.
CONTACT INFORMATION
- -------- --- ------------------------------------ ----------Regional Offices
See Regional Communicable Disease contacts on pages 15-20
Headquarters
WHO Division of Control of Tropical Diseases, Dracunculiasis Eradication Unit (CTD/DRA)
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: ranquep@who.ch / cattandp@who.ch
Tel: (41 22) 791 3874 / 3880/ 4743/ 3875/ 2111
Fax: (41 22) 791 4777 / 0746 attn CTD/DRA
WHO Recommended Surveillance Standards
October 97
40
A98.3, A98.4
Et.ola-Mart.urg viral diseases
. areas of African
______ _____ __________ _
sSlsIgSls^pncAsToEPlN'^'^
110
s “diarrhfee rouge m
show
irnnolence,
1
criteria for diagnosis
I Laboratory
and/or IgM)’ or
lfety level 4) or
con-'B:^^sS”r
,
positive PCS
• -OTpalW w»>«» d'n'Ca‘
| Case classification
A case that is c<
\ Suspected.
in epidemiI Probable:
. Any person
fever, or
pniiny ____
’
p,es.nW9 »* aeuK
etiie uia**—
abdominal pa‘n’»
Confirmed'.
Contact-
i
S^SS«Es=3;:;;
^ere ls^
handling of potential y
and after
suff.cjent for
suspected or P^
S'Z^SScontfirmation and the
control purpose.
41
October 9*7
nded Surveillance Standards
WHO Recommen
• ^<1
/ ^ECOMME,
/ n endemic N^Dty^—
I lrri^ediate report
r~
in th
ensure rapidepo
inv(^gofsuSi
-’^tigatioi
Note:
routine surveiHo'ance ofEHFr.
haem°rrhagicfev
i
Neg------ ----
,
~~
0 eP'demjc
____________
^E^.o„emea(ateaM
,ev',s'°
be Wer.
Iln e^-ic situat.
'S ,e'9' Cr—co^-rout,e ,
’^nso. La
’ '^ns/fied su al'°n:
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. ;S°lat'°n. and of ^ and active find'
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/
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c°nfirmed)
_____________
•
S2feM
/
8reakd(
0Wnbys^andageg
/ Contacts
^^^LCQQort
’>“““^bepTOael
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/
a‘r froper/ai
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, ’ !"’“’”=«^b.PTOaM
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'butlonofc^esandcontacts
Case fatality rate.
ded'
^-'o/oXaVassess^ rates’
A more detaifed rn ® Sment- /nda9e'SPeC'fca^ rates CouWb^
''Wsto““b"«v5S““b;
'e ^culated fOr
J
October 97
■' ■.
■>
data and a
c°rnplete
St^ndards
?
as a s^Ple epidemic
If
.v? •
Wop«e
S?: sjsx-»'
I ActivXsefading. and
I
’or
*"
or an
.=-p
\
of an outbreak
|
the P«w'"“.Sremrt ™re.»
_____
“ b°m
-------------------------
,comm^eDl—
Regional offices
and Control (EMC)
s«^H.a<Wrte7 of erergWP »"a “"“("s
e-rrf ratf™®^09 / 25T3 <2’!’ mc
43
October 91
ended Surveillance Standards
WH0 Recommended
Japanese Encephalitis
A 83.0
Japanese Encephalitis
RATIONALE FOR SURVEILLANCE
Over a large part of East Asia, Japanese encephalitis (JE) virus is the most common cause of
encephalitis. This mosquito-borne encephalitis has the potential for outbreaks and can be .
associated with a high case fatality rate. Based on the natural transmission cycle of Japanese
encephalitis, three strategies for control have been proposed: vector control, vaccination of swine
and vaccination of humans. Surveillance should target these elements.
RECOMMENDED CASE DEFINITION
Clinical description
Japanese encephalitis virus infection may result in a febrile illness of variable severity associated
with neurological symptoms ranging from headache to meningitis or encephalitis. The encephalitis
can not be distinguished clinically from other central nervous system infections. Symptoms can
include: headache, fever, meningeal signs, stupor, disorientation, coma, tremors, paresis
(generalised), hypertonia, loss of co-ordination.
Laboratory criteria for diagnosis
Presumptive: Detection of an acute phase anti-viral antibody response by one of the following:
• Isotype-capture immunoassay to detect IgM to the virus in serum.
• A fourfold or greater rise in specific antibody in paired sera by hemagglutination-inhibition test*
• A fourfold or greater rise in specific antibody in paired sera by plaque reduction neutralisation
test*
Confirmative:
Virus detection (by isolation of virus or immunocytochemistry or immunofluorescence or RT-PCR)
or detection of an acute-phase anti-viral antibody response by Isotype-capture immunoassay to
detect IgM to the virus in CSF.
‘Cross-reactions to dengue and other flaviviruses must be controlled.
Note: JE infections are common and the majority are asymptomatic. JE infections may occur
concurrently with other infections causing CNS symptoms and serological evidence of recent
JE viral infection may not be correct in indicating JE to be the cause of the illness.
Case classification
A case that is compatible with the clinical description
Suspected:
A suspected case with presumptive laboratory results
Probable:
A suspected case with confirmative laboratory results
Confirmed:
recommended types of surveillance
Areas where no Japanese encephalitis transmission has been detected but where the vector
is present.
Surveillance for acute CNS syndromes; investigation of clusters with fever
Countries where disease is endemic with seasonal increases in transmission and areas
where epidemic Japanese encephalitis is occurring
Routine weekly/monthly reporting of aggregated data on suspected, probable and confirmed cases
from peripheral to intermediate and central level
RECOMMENDED MINIMUM DATA ELEMENTS
Case-based data at the peripheral level:
Case classification (suspected/probable/confirmed), unique identifier, name of patient, age, sex,
geographical information, date of onset, 2 week travel history, hospitalisation (Y/N), outcome
45
WHO Recommended Surveillance Standards
October 97
Aggregated data for reporting:
Number of cases by age group
Number of suspected /confirmed cases
Number of hospitalisations and deaths
RECOMMENDED DATA ANALYSES, PRESENTATION, REPORTS'
Number of cases and deaths by geographic area
Number of hospitalisations
Case fatality
PRINCIPAL USES OF DATA FOR DECISION MAKING
• To target high risk areas for intervention
To monitor changes in epidemiology and pattern of disease
o monitor trends in endemic disease or re-emergence of disease
• To monitor vaccine efficacy
SPECIAL ASPECTS
None
CONTACT INFORMATION
------------------ —
Regional offices
See Regional Communicable Disease contacts on pages 15-20
Headquarters
^fnue'Spia^S
DiS6aS®S Surveillan« and Controi (EMC)
E-mail: arthurr@who.ch / outbreakemc@who ch
Tel: (41 22) 791 2658 / 2850 / 2111
Fax: (41 22) 791 4878
WHO Recommended Surveillance Standards
October 97
46
Lymphatic filarias is
B74
Lymphatic filariasis
RATIONALE FOR SURVEILLANCE
Lymphatic filariasis remains a major cause of clinical morbidity in much of Asia, Africa, the Western
Pacific and certain parts of the Americas. It is the second leading cause of permanent long-term
disability. The prevalence is increasing world-wide with at least 120 million people affected at
different stages of the disease. Both diethylcarbamazine (DEC) and ivermectin have been shown to
be very effective in reducing microfilaraemia. Selected by the International Task Force for Disease
Eradication as one of six potentially eradicable infectious diseases. WHO policy is to achieve better
control and aim for disease elimination in human using drug combinations in mass populations
complemented by vector control. Therefore surveillance is essential.
RECOMMENDED CASE DEFINITION
Clinical case definition
Hydrocoele or lymphoedema in a resident of an endemic area for which other causes of these
findings have been excluded
Laboratory criteria for diagnosis
Microfilaria positive, antigen positive or biopsy positive
Case classification
Not applicable
Suspected
A case that meets the clinical case definition
Probable:
A probable case that is laboratory-confirmed
Confirmed:
RECOMMENDED TYPES OF SURVEILLANCE
>
There are currently three options and the choice will depend on the local situation:
• Routine monthly reporting of aggregated data on probable and confirmed cases from periphery
to intermediate level and to central level or
• sentinel population surveys (standardised and periodically) or
• Active case finding through surveys of selected groups or mass surveys
International: Annual reporting from central level to WHO (only a limited number of countries)
WHO Recommended Surveillance Standards
October 97
47
RECOMMENDED MINIMUM DATA ELEMENTS
Case-based data at peripheral level
Case classification (probable/confirmed)
Unique identifier
Geographical information (location)
Laboratory result
Aggregated data for reporting
Number of new cases
Number of laboratory-confirmed cases
Number of chronic conditions (hydrocoele or lymphoedema)
recommended data analyses, presentation, reports'
Number of cases by geographical area and by year
• Monthly and yeariy incidence, point prevalence (if active
case detection), by geographic origin,
by sex, by parasitological diagnosis
PRINCIPAL USES OF DATA FOR DECISION MAKING
i^'rnate m^9nitude of the Problem and define populations at risk
• Improve and focus the control activities
ma"a9Tlent and follow-uP °f Rlariasis infected patients
Identify technical and operational difficulties
SPECIAL ASPECTS
None
----------------
:
CONTACT INFORMATION---------------------------------------------------------------- Regional offices
1
See Regional Communicable Disease contacts on pages 15-20
Headquarters
e— u"“ ™
?! K
E-mail: ottesene@who.ch / ctd@who ch
>
Tel: (41 22) 791 3225 / 2726 / 2111
Fax: (41 22) 791 4893 / 0746 attn CTD
WHO Recommended Surveillance Standards
October 97
48
Acute viral hepatitis
B15-B17
Acute viral hepatitis
RATIONALE FOR SURVEILLANCE---------------------------------------------------------------------------• Use aggregated data to detect outbreaks and their cause• Use various sources, in addition to surveillance data, to determine the impact of various types of
viral hepatitis in the population and prioritise them among other diseases of public health
importance
• Use hepatitis B immunization coverage data to monitor progress towards control of hepatitis B
Hepatitis B is targeted by WHO for reduced incidence/prevalence (9GPW6.3)
RECOMMENDED CASE DEFINITION
-------- ------------ ---- -
Clinical description
An acute illness that includes acute jaundice, dark urine, anorexia, malaise, extreme fatigue and
right upper quadrant tenderness.
.
’
N.B. Most infections during early childhood and a variable proportion of adult infections are
asymptomatic.
Laboratory criteria for diagnosis
• Hepatitis A: IgM anti-HAV positive
■~“
• Hepatitis B: HBsAg positive or IgM anti-HBc-positive, and IgM anti-HAV
negative (if available)
• Hepatitis E: IgM anti-HEV positive and IgM anti-HAV negative, and HBsAg
negative or IgM anti-HBc negative
Note:
Further testing of patients who are negative for markers of acute hepatitis A, B and E can be used
to make a diagnosis of acute hepatitis C or D. Laboratory criteria for hepatitis C in patients with nonA non-B hepatitis are as follows:
•
•
Hepatitis C: Anti-HCV positive
Hepatitis D: only occurs as co-or superinfection of hepatitis B: HBsAg positive or
IgM anti-HBc positive plus anti-HDV positive
Case classification
Suspected:
A case that is compatible with the clinical description
Probable:
Not applicable
Confirmed:
A case that is laboratory-confirmed or,
for hepatitis A and E: a case that is compatible with the clinical description and
occurs in a person who has an epidemiological link with a person who has
laboratory-confirmed hepatitis A/ E (i.e., household or sexual contact with an
infected person) during the 15-50 days before the onset of symptoms
RECOMMENDED TYPES OF SURVEILLANCE
- ---------Routine monthly reporting of aggregated data of suspected or confirmed cases from peripheral level
to intermediate and central level.
All outbreaks should be investigated immediately and confirmed serologically.
International: The aggregated data of probable or confirmed cases from national reports are
reported monthly to the WHO regional offices.
RECOMMENDED MINIMUM DATA ELEMENTS
'
Aggregated data for reporting
Number of cases
Number of third doses of hepatitis B vaccine (HBV3) administered to infants
WHO Recommended Surveillance Standards
October 97
49
RtPUH'^
muKipiescadc. e,
Number of acute viral hepatitis cases by etiologic agent, where possible
HB immunizaTn
m°nth’ 9e°9raphical area’ and
data exist) age group
anti-HCV positive (see special aspects)
PRINCIPAL USES OF DATA FOR DECISION-MAKING------------------------• Investigate all suspected/reported outbreaks
• OUtSs) To SCn-^USe °f aCUte Viral hePatitiS CaSeS (rePOrted r0Utinely °r durin9
ouioreaKs), so that corrective measures can be taken
•
•
Monitor HB immunization coverage to measure programme performance
SPECIAL ASPECTS
------------------------ ------------------ ------------------------acut® vira' hapatitis from developing countries should be interpreted with
^rnlnnirDt«t
tyPeS
ral hepatitis (A to E) based on clinical diagnosis is unreliable and
tn hT9 7
9 15 TC MSary f°r accurate diagnosis. Many developing countries do not have access
»'=“•=«
TXn!90611^ °f Hepatitis B’ C and D infection include chronic carrier state, chronic hepatitis
cirrhosis, and primary liver cancer. Measuring the impact of these conditions requires data collection
diSSXT^
dis:ase ePidemioio9ist3. ncluding hospital
discharge and mortal ty data and cancer registers. Special sero-prevalence surveys may be needed
° S"bMZ
H,BV M HCV
"tte
w«»"
1" special groups
seroconversion in children is not necessary in most countries.
CONTACT INFORMATION
- ----------------- --------------------------------- ----------------------Regional offices
See Regional Communicable Disease contacts on pages 15-20
Headquarters
WHO Global Programme for Vaccines and Immunization (GPV)
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: kanem@who.ch / gpv@who ch
Tel: (41 22) 791 4408 / 4410 / 2111
Fax: (41 22) 791 07 46 attn GPV
Other Communicable Dlse^es Surveillance and Control (EMC)
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: lavanchyd@who.ch / outbreakemc@who ch
Tel: (41 22) 791 2656 / 2850 / 2111
Fax: (41 22) 791 4878 EMC
WHO Recommended Surveillance Standards
October 97
50
HIV
B20-B24
HIV Infection
(Human immunodeficiency virus)
RATIONALE FOR SURVEILLANCE
The surveillance of HIV infection is the best way to forecast the future impact of AIDS patients on
national health resources. It may also allow counselling, follow-up and chemoprophylaxis when
appropriate at an individual level.
RECOMMENDED CASE DEFINITION
Clinical description
There is no clinical description, the diagnosis is based on laboratory criteria
Laboratory criteria for diagnosis
HIV positive serology (ELISA)
Confirmation by second serological test necessary only in settings with estimated HIV prevalence
lower than 10%.
Confirmation should be a second ELISA or simple/rapid assay based on a different antigen
preparation and/or different test principle
Case classification
Not applicable
Suspected:
Probable:
Not applicable
A laboratory-confirmed case
Confirmed:
Note:
Except for unlinked anonymous testing, serological testing should only be done in
combination with appropriate pre- and post-counselling services.
Western Blot is used for individual confirmation rather than general HIV survey, in countries which
have the appropriate resources.
RECOMMENDED TYPES OF SURVEILLANCE
The method of preference is unlinked anonymous seroprevalence testing in sentinel sites. In order
to monitor time trends, it is necessary to ensure continuity of the same sentinel surveillance sites
over time, and that within sites the same sampling scheme is used over time (periodically and
standardised).
For countries with very low prevalence, the sentinel sites should focus on testing of high risk groups
(patients seeking treatment for STDs or for intravenous drug use, or prostitutes seeking health care
treatment etc.) For countries with higher prevalence: High risk groups should continue to be
monitored, and surveillance of general population groups such as pregnant women attending
antenatal clinics should be carried out.
Routine yearly reporting of aggregated data of confirmed cases from each sentinel site to
intermediate and unchanged to central level.
Some countries report case-based data.
Other sources of data:
• Hospital
• Dermatologist
• STD clinics
• Blood bank
• Army (data from army recruits)
• Special surveys
• Mortality reports
i-
{'Of
WHO Recommended Surveillance Standards
October 97
I A
' I >i S'31 o ’
unh
2 I
51
RECOMMENDED MINIMUM DATA ELEMENTS
----------------------- ----------Case-based data for reporting:
Age, sex, location, risk factor (e.g. blood transfusion, intravenous drug use, multiple sexual
partners)
Aggregated data for reporting:
On a yearly basis: number of cases tested by age, by sex, by risk factors
RECOMMENDED DATA ANALYSES, PRESENTATION, REPORTS
- ----• Analysis of prevalence by age and sex and geographic area, rural/urban locations and
population subgroups, risk factors
• Analysis of trends in prevalence over time, by age and sex and geographic area, rural/urban
location and population subgroup
• Graphs and tables: Prevalence and confidence intervals, by year, age and sex, by sentinel site,
population subgroup, geographic area, rural/urban location
• Maps: prevalence levels at each sentinel site
PRINCIPAL USES OF DATA FOR DECISION MAKING
"————————
• Assess the current magnitude, and current trends of the HIV/AIDS epidemic
• Project the number of AIDS cases over the next decade
• Identify high risk population sub-groups and/or geographic areas for intervention
• Evaluate the impact of specific interventions
• Assess impact on health services, plan health and social service activities for people with
HIV/AIDS
• Increase public and political awareness of the disease
SPECIAL ASPECTS
None
CONTACT
Regional offices
See Regional Communicable Disease contacts on pages 15-20
Headquarters
UNAIDS/WHO Technical Working Group on Global HIV/AIDS and STD Surveillance
WHO, 20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: surveillance@unaids.org
Tel: (41 22) 791 2380/4551
Fax: (41 22) 791 4198
WHO Recommended Surveillance Standards
October 97
52
Influenza
J10, J11
Influenza
RATIONALE FOR SURVEILLANCE
- --------------Surveillance of influenza is essential for the early detection and evaluation of new variants or
subtypes of influenza virus. The early detection and characterization of these viruses allows for
timely annual updates of a vaccine which can prevent deaths and alleviate illness in vulnerable
groups of the population.
RECOMMENDED CASE DEFINITION
Clinical case definition
A person with sudden onset of fever of >39OC, respiratory symptoms, myalgia and headache
Laboratory criteria for diagnosis
Virus isolation: recommended naso-pharyngeal smear or
direct detection of influenza viral antigen
Case classification
Suspected:
A case that meets the clinical case definition
Probable:
A case that meets the clinical case definition and is epidemiologically linked to a
laboratory-confirmed case
Confirmed:
A case that meets the clinical case definition and is laboratory-confirmed
RECOMMENDED TYPES OF SURVEILLANCE
Routine weekly (at least for the epidemic period) reporting of case-based or aggregated data of
• suspected/probable/confirmed cases by sentinel practices (general practitioners)
• confirmed cases by laboratory
to central level
International: weekly aggregated data on confirmed cases from countries to WHO (FluNet)
accompanied by information on extent of activity in the community.
RECOMMENDED MINIMUM DATA ELEMENTS
Case-based data for reporting:
Case classification (suspected/probable/confirmed)
Sub-type of virus (if known)
Unique identifier, age, geographical area
Date of onset
Vaccination status
Outcome (recovered/complications/death)
Aggregated data for reporting:
For every geographical area (country) and every week: number of cases by age groups, sub
type of virus (if known), outcome
Case-based laboratory data:
Laboratory number, specimen date (day/month), patient age (years or months), city, state or
province of origin of patient, isolation system, type, subtype, isolate designation, resembles
reference strain (Y/N), is further identification in progress (Y/N), forwarded to WHO collaborating
centre(Y/N)
RECOMMENDED DATA ANALYSES, PRESENTATION, REPORTS
Graphs: Number of cases by week, age group, virus sub-type
Tables: Number of cases by week, age group, geographical area, virus sub-type, outcome
Maps: Number of cases by week, geographical area, country
WHO Recommended Surveillance Standards
October 97
53
PRINCIPAL USES OF DATA FOR DECISION MAKING
• Rapid isolation and antigenic characterization of influenza viruses for planning the formulation of
vaccine for the following season
• Early detection of influenza epidemics thus enabling the implementation of public health
measures such as immunization of risk groups and planning for the possible impact on essential
services
• Morbidity and mortality data to estimate the impact and costs of the outbreak and control
measures such as vaccination campaigns
SPECIAL ASPECTS
The speedy provision of isolates to the WHO Collaborating Centres is crucial.
Laboratory surveillance is most specific and the cornerstone of surveillance.
Sentinel surveillance (by general practitioners) on influenza-like illness is less specific but sensitive
and rapid.
CONTACT INFORMATION
Regional offices
See Regional Communicable Disease contacts on pages 15-20
Headquarters
WHO Division of Emerging and other Communicable Diseases Surveillance and Control (EMC),
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: lavanchyd@who.ch / outbreakemc@who.ch
Tel: (41 22) 791 2656 / 2850 / 2111
Fax: (41 22) 791 4878 / 0746 attn EMC
WHO Recommended Surveillance Standards
October 97
54
Lassa fever
A96.2
Lassa fever
RATIONALE FOR SURVEILLANCE
This severe acute viral infection has the potential to produce epidemics, and as such surveillance
mechanisms to detect outbreaks and monitor control measures are critical in affected countries.
RECOMMENDED CASE DEFINITION
Clinical description:
An illness of gradual onset with: malaise, fever, headache, sore throat, cough, nausea, vomiting,
diarrhoea, myalgia, and chest pain, hearing loss, and a history of contact with excreta of rodents
Laboratory criteria for diagnosis;
• Isolation of virus (only in laboratory of biosafety level 4) from blood, urine or throat washings or
• Positive IgM serology or seroconversion (IgG antibody) in paired serum specimens or
• Demonstration of Lassa virus antigen in autopsy tissues by immunohistochemistry or in serum by
ELISA
• Positive PCR from serum or autopsy tissues
Case classification.
Suspected:
A case compatible with the clinical description
Probable:
A suspected case that is epidemiological linked to a confirmed case
Confirmed:
A suspected case that is laboratory-confirmed
Contact:
A person having close personal contact with the patient (living with, caring for) or a
person testing the laboratory specimens of a patient in the three weeks after the
onset of the illness
RECOMMENDED TYPES OF SURVEILLANCE
Endemic situation:
Immediate reporting of case-based data of suspected, probable or confirmed cases from peripheral
level to intermediate and central level.
All cases must be investigated, and contact tracing undertaken.
Routine monthly reporting of aggregated data from intermediate to central level.
Outbreak situation:
All suspected outbreaks must be reported centrally. Surveillance must be intensified with active
case finding and contact tracing. Aggregated data on a daily/weekly basis to be submitted to
intermediate and central level by investigation team.
Disease is endemic in Sierra Leone, Liberia, Guinea and regions of Nigeria. Outside these areas,
compatible symptoms with a history of travel to or arrival from one of these countries should prompt
investigation and reporting.
WHO Recommended Surveillance Standards
October 97
55
RECOMMENDED MINIMUM DATA ELEMENTS
Case-based data for reporting and investigation
Case classification (suspected/probable/confirmed)
Unique identifier, age, sex, place of residence for the three weeks before onset of illness
Date of onset
Hospitalisation
Outcome
Contact with case, contact with rodents, contacts since onset of illness
Aggregated data for reporting
Endemic situation
Number of cases (suspect/probable/confirmed) by geographical area and outcome
Contacts by geographical area, success of tracing and outcome
Outbreak situation
Total number of cases by village, geographical area, onset date, hospitalisation, outcome
New cases and contacts identified since last report
Total number of contacts by outcome
New contacts identified and traced since last report
RECOMMENDED DATA ANALYSES, PRESENTATION, REPORTS
•
Mapping number of cases by geographical area
• Percentage of contacts followed up
• Case fatality rate
4
PRINCIPAL USES OF DATA FOR DECISION MAKING
• Monitoring endemic disease over time
• Identification of risk groups or areas
• Identification of clusters/outbreaks
• Investigation of cases, contacts and source of infection
SPECIAL ASPECTS:
Extreme biohazard associated with sample, transport and with laboratory investigations.
___ _____________________ 1
CONTACT INFORMATION
Regional offices
See Regional Communicable Disease contacts on the pages 15-20
Headquarters
WHO Division of Emerging and other Communicable Diseases Surveillance and Control (EMC)
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: arthurr@who.ch / outbreakemc@who.ch
Tel: (41 22) 791 2658 / 2850 / 2111
Fax: (41 22) 791 48 78 / 07 46 attn EMC
WHO Recommended Surveillance Standards
October 97
56
Legionellosis
A48.1
Legionellosis (Legionnaire disease, Legionnaires’ pneumonia)
RATIONALE FOR SURVEILLANCE
Legionnaire disease is a disease with epidemic potential and high case fatality. Surveillance is
important in order to detect epidemics and to institute appropriate investigations and control,
measures. In addition the surveillance of sporadic disease may provide clues to disease etiology
and prevention.
RECOMMENDED CASE DEFINITION
Clinical description
A illness characterised by an acute lower respiratory infection with focal signs of pneumonia on
clinical examination and/or radiological evidence of pneumonia
Laboratory criteria for diagnosis
Presumptive: one or more of the following:
• Detection of specific legionella antigen in respiratory secretion or urine
• Direct fluorescent antibody (DFA) staining of the organism in respiratory secretion or lung tissue
using evaluated monoclonal reagents
• A fourfold or greater rise in specific serum antibody titre to legionella species other than
Legionella pneumophila serogroup 1, using a locally validated serological test
Confirmative: one or more of the following:
• Isolation of Legionella from respiratory secretions, lung tissue, pleural fluid, blood or other
normally sterile fluids
• A fourfold or greater rise in specific serum antibody titre to Lpneumophila serogroup 1 by
indirect immunofluorescence antibody test or microagglutination
Case classification
Not applicable
*
Suspected:
A case that is compatible with the clinical description with presumptive laboratory
Probable:
results
A case that is compatible with the clinical description with confirmative laboratory
Confirmed:
results
Note:
Some countries (e.g. USA, UK) now include the detection of L pneumophila serogroup 1
antigen in urine as a confirmatory test
RECOMMENDED TYPES OF SURVEILLANCE
Immediate reporting of case-based data from periphery to intermediate and central level.
The identification of cases should prompt immediate investigation for risk factors and other cases.
(For a rapid response, active case finding is preferred).
International: Since travel and stays in hotels are important risk factors, effective international
surveillance is essential to identify and control the point source of infections.
Legionella infection is usually diagnosed after the patient’s return to the country of
residence with the likelihood of it being considered as a sporadic, single case.
A surveillance scheme as the European Working Group for Legionella Infections*
(see special aspects) allows the detection of clusters of cases (>2 cases) with the
same source of transmission, as case notifications from different European
countries are collected in the same database.
WHO Recommended Surveillance Standards
October 97
57
RECOMMENDED MINIMUM DATA ELEMENTS
"
------------Case-based data for investigation and reporting:
Unique identifier, name, age, sex. geographical information, date of onset, outcome
Underlying risk factors (e.g. immunocompromised patient, AIDS)
Exposure risk factors (hospitalisations, hotels, or other accommodation and travel history during
the two weeks before the onset)
Laboratory data (specimen type, date collected, Legionella spp. isolated)
RECOMMENDED DATA ANALYSES, PRESENTATION, REPORTS------------------- ---------------------• Review data regularly to look for clusters of cases in time, place or person (this should be
undertaken at all levels) • Incidence of infection by month, geographical area, age group, risk factors, exposure factors
PRINCIPAL USES OF DATA FOR DECISION MAKING
• Detect clusters/outbreaks
• Identify high risk areas and exposures
• Monitor impact of environmental control measures
- ---------------------------
SPECIAL ASPECTS
“
----------------------- —----------------------------• Two currently recognised, distinct clinicoepidemiologic manifestations: “Legionnaires’ disease"
(pneumonic form) and “Pontiac fever^non-pneumonic form). Both are characterised initially by
anorexia, vomiting, myalgia and headache, followed within a day by rising fevers and chills. In
the pneumonic form non-productive cough, abdominal pain/diarrhoea, confusion/delirium are
common. It is not possible, clinically, to distinguish Legionella pneumonia from other pneumonia.
Suspicion, however, should be raised in any pneumonia connected with epidemiological
information (e.g., recent travelling, hospitalisation, gatherings, immunosuppression). In addition,
age (> 40), sex (M), smoking, alcohol consumption have been shown to be risk factors. The
reservoir of Legionella spp. is probably primarily aqueous (e.g., hot water systems, airconditioning, cooling towers and evaporative condensers). Pontiac fever is not associated with
pneumonia. It is thought to represent a reaction to inhaled antigen, rather than to bacteria.
• Environmental surveillance for Legionella in water sources can be undertaken usually as part of
registration and licensing procedures. In the absence of these measure environmental
surveillance should be at least undertaken for known sources of outbreaks to ensure that the
organism is eradicated.
• * European Working Group or Legionella Infections
*
PHLS Communicable Disease Surveillance Centre
61 Colindale Avenue, London NW9 SEC
Tel: (44) 181 200 6868
E-mail: respedsc@PHIS.co.uk
Fax: (44) 181 200 7868
CONTACT INFORMATION
- -------------------------------------------Regional offices :
See Regional Communicable Disease contacts on pages 15-20
Headquarters:
WHO Division of Emerging and other Communicable Diseases Surveillance and Control (EMC)
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: tikhomirove@who.ch / outbreakemc@who.ch
Tel: (41 22)791 2656/2850/2111
Fax: (41 22) 791 4878 / 0746 attn EMC
_______________
WHO Recommended Surveillance Standards
October 97
58
«
Cutaneous leishmaniasis
B55.1, B55.2
Cutaneous leishmaniasis
RATIONALE FOR SURVEILLANCE
Cutaneous leishmaniasis (CL) is endemic in 72 countries. The yearly incidence is estimated at
1 500 000 cases. The disease has several clinical forms: localised CL, diffuse CL (DCL).the most
difficult to treat, and mucocutaneous leishmaniasis (MCL) which is the most severe form as it
produces disfiguring lesions and mutilations of the face. In CL anthroponotic foci, where man is
believed to be the sole reservoir, epidemics are linked to human migrations from rural to poor
suburban areas; In zoonotic foci, where mammals are reservoirs, epidemics are related to
environmental changes and movement of non-immune people to rural areas.
In establishing disease impact and monitoring efforts towards disease control and detecting
epidemics, surveillance is essential.
RECOMMENDED CASE DEFINITION
Clinical description
Appearance of one or more lesions on uncovered parts of the body. The face, neck, arms and legs
are the most common sites. At the site of inoculation a nodule appears, enlarges and becomes an
indolent ulcer. The sore remains in this stage for a variable time, before healing, and leaving a
depressed scar. In some individuals, certain strains can disseminate and cause mucosal lesions.
These sequelae involve nasopharyngeal tissues and can be very disfiguring.
Laboratory criteria for diagnosis
• positive parasitology (stained smear or culture from the lesion)
• only for MCL: positive serology (IFA, ELISA)
Case classification
WHO operational definition:
A case of CL is a person showing clinical signs (skin or muco-cutaneous lesions) with
parasitological confirmation of the diagnosis (positive smear or culture) and/or, for MCL only,
serological diagnosis
RECOMMENDED TYPES OF SURVEILLANCE
At peripheral level individual patient records should be retained for investigation and case
management.
Routine monthly reporting of aggregated data of cases from periphery to intermediate and central
level.
International: annual reporting from central level to WHO (limited number of countries).
Active case finding through surveys of selected groups or mass surveys (standardised and
periodically) are an alternative to estimate the prevalence of CL.
WHO Recommended Surveillance Standards
October 97
59
RECOMMENDED MINIMUM DATA ELEMENTS
------------------- Individual patient records at peripheral level:
Identification data:
Unique identifier, age, sex, geographical information, past travels, duration
at residence
Leishmaniasis data:
clinical features, date of diagnosis, serological (for MCL only) and
parasitological diagnosis, Leishmania species, treatment outcome
Aggregated data for reporting:
Number of cases by age, sex, type of diagnosis
RECOMMENDED DATA ANALYSIS, PRESENTATION, REPORTS
Tables: Incidences by geographical area, by age, by sex, by type of diagnosis, by month /year
Point prevalence (if active case detection).
Maps: Incidence by village
PRINCIPAL USES OF DATA FOR DECISION MAKING
Evaluate the real extent of the problem and the main populations at risk
Improve and focus the control activities
Improve the management and follow-up of CL /DCL and MCL patients (WHO guidelines)
Identify technical and operational difficulties
Evaluate impact of control interventions
Anticipate epidemics
SPECIAL ASPECTS
CL tends to be grossly underestimated as most of the official data are obtained through passive
case detection only. Other factors which lead to misdiagnosis or non-diagnosis are: wide scatter of
foci, limited access to medical facilities, scarcity of diagnostic facilities and limited or irregular
availability of first-line drugs
CONTACT INFORMATION:
Regional offices :
See Regional Communicable Disease contacts on the pages 15-20
Headquarters:
Division of Control of Communicable Diseases (CTD)
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: desjeuxp@who.ch
Tel: (41 22) 791 38 70
Fax: (41 22) 791 4777 attn CTD/TRY
4
WHO Recommended Surveillance Standards
October 97
60
Leishmania/HIV co-infections
Leishmania/HIV co-infections
RATIONALE FOR SURVEILLANCE:
Leishmania/HIV co-infections have already been reported from 22 countries. The overlap of visceral
leishmaniasis (VL) and AIDS is on the increase due to the spread of the AIDS pandemic in rural
areas and that of VL in suburban areas. In southern Europe 25% - 70 % of adult VL cases are
related to HIV infection and 1.5-9 % of AIDS cases suffer from newly acquired or reactivated VL
RECOMMENDED CASE DEFINITION
WHO operational definition:
A case of co-infection is a HIV positive person showing clinical signs of leishmaniasis (visceral or
cutaneous) with parasitological confirmation of the diagnosis
RECOMMENDED TYPES OF SURVEILLANCE
Sentinel surveillance by hospital and/or laboratories
At peripheral level, hospitals and laboratories, members of the network of surveillance (from 10
countries at the time of writing) maintain individual patient records. They use guidelines for diagnosis
and a standardised case report form recently computerised.
Routine aggregated or case-based data of all cases reported every six months from peripheral level
or central level to WHO
World-wide information collected, processed and rediffused (twice per year) by the central registry
set up at WHO (CTD/TRY)
RECOMMENDED MINIMUM DATA ELEMENTS
Case-based data for individual patient record at peripheral level and for reporting:
Identification data:
Unique identifier, age, sex, geographical information, travel history, duration
at residence;
>
Leishmaniasis data:
Date of diagnosis, serological and parasitological diagnosis, Leishmania
species, clinical features; HIV data: date of diagnosis, serology, CD4/mm3,
risk groups, AIDS-defining diseases; treatment outcome.
Aggregated data:
Number of cases by age, sex, type of diagnosis, risk group
4.
RECOMMENDED DATA ANALYSIS, PRESENTATION, REPORTS
Geographic distribution, sex distribution, age distribution, risk groups, main risk groups by country,
date of HIV diagnosis, date of Leishmaniasis diagnosis, correlation between leishmaniasis and HIV
diagnosis, immunological parameters, parasitological diagnosis, clinical diagnosis stage, clinical
features and AIDS-defining diseases
PRINCIPAL USES OF DATA FOR DECISION MAKING
• Evaluate the real extent of the problem and the main population at risk
• Irnprove the management and follow-up of co-infected patients by the use of the guidelines
• Identify technical and operational difficulties faced by the network of institutions
• Evaluate impact of intervention
SPECIAL ASPECTS
A network helps
• to improve the reliability of data collection by the use of the standardised case report form
• to improve the co-ordination between the institutions
• to improve the active medical surveillance of the main population at risk
WHO Recommended Surveillance Standards
October 97
61
CONTACT INFORMATION
Regional offices :
See Regional Communicable Disease contacts on pages 15-20
Headquarters:
Division of Control of Communicable Diseases (CTD)
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: desjeuxp@who.ch
Tel: (41 22) 791 38 70
Fax: (41 22) 791 4777 attn CTD/TRY
WHO Recommended Surveillance Standards
October 97
62
Visceral leishmaniasis
B55.0
Visceral leishmaniasis
RATIONALE FOR SURVEILLANCE:
Visceral leishmaniasis (VL) is endemic in 61 countries. The yearly incidence is estimated at 500 000
cases. It is the most severe form of leishmaniasis as it can be fatal in the absence of treatment
Deadly epidemic frequently occur in VL anthroponotic foci of Bangladesh, India, Nepal and Sudan,
where man is believed to be the sole reservoir. In establishing disease impact and monitor efforts
towards disease control and detecting epidemics, surveillance is essential.
RECOMMENDED CASE DEFINITION
Clinical description
An illness with prolonged irregular fever, splenomegaly and weight loss as its main symptoms
Laboratory criteria for diagnosis
• positive parasitology (stained smears from bone marrow, spleen, liver, lymph node, blood or
culture of the organism from a biopsy or aspirated material)
•
positive serology (IFA, ELISA)
Case classification
WHO operational definition:
A VL case is a person showing clinical signs (mainly prolonged irregular fever, splenomegaly and
weight loss) with serological (at geographical area level) and /or parasitological confirmation (when
feasible at central level) of the diagnosis. In endemic malarious areas, VL should be suspected when
fever lasts for more than two weeks and no response has been achieved with anti-malaria drugs
(assuming drug-resistant malaria has also been considered)
RECOMMENDED TYPES OF SURVEILLANCE
Routine monthly reporting of aggregated data from periphery to intermediate and central level.
International: annual reporting from central level to WHO (only a limited number of countries)
Active case finding through surveys of selected groups or mass surveys (standardised and
periodically) are an alternative to estimate the prevalence of VL.
RECOMMENDED MINIMUM DATA ELEMENTS
Individual patient records at peripheral level:
Unique identifier, age, sex, geographical information, past travels, duration
Identification data:
residence
at
Clinical features, date of diagnosis, serological and parasitological
Leishmaniasis data:
diagnosis, Leishmania species, treatment outcome
Aggregated data for reporting:
Number of cases by age, sex, type of diagnosis
RECOMMENDED DATA ANALYSIS, PRESENTATION, REPORTS
Tables: Incidences by geographical area, by age, by sex, by type of diagnosis, by risk group, by
clinical features, by month /year
point prevalence (if active case detection)
WHO Recommended Surveillance Standards
October 97
63
PRINCIPAL USES OF DATA FOR DECISION MAKING------------------------• Evaluate the real extent of the problem and the main populations at risk
• Improve and focus the control activities
• Identify technical and operational difficulties.
• Evaluate impact of control interventions
• Anticipate epidemics
SPECIAL ASPECTS
------------------------------------------------------------VL tends to be largely underreported as most of the official data are obtained through passive case
detection only. The number of people exposed to infection or infected without any symptoms is much
more important than the number of detected VL cases.
CONTACT INFORMATION
Regional offices :
See Regional Communicable Disease contacts on pages 15-20
Headquarters:
Division of Control of Communicable Diseases (CTD)
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: desjeuxp@who.ch
Tel: (41 22) 791 38 70
Fax: (41 22) 791 4777 attn CTD/TRY
WHO Recommended Surveillance Standards
October 97
64
Leprosy
A30
Leprosy
(Hansen Disease)
RATIONALE FOR SURVEILLANCE
Leprosy continues to affect a large number of people. In 1995 there were an estimated 1.8 million
cases in the world. Control of the disease recently improved with the introduction of Multidrug
therapy. WHO has targeted the disease for elimination (<1 case / 10 000 population) by the year
2000 through a focused flexible approach (9GPW 6.2). This includes making MDT available to all
communities and areas, appropriate and good quality diagnosis and treatment with evaluation
through epidemiological surveillance and programme monitoring.
RECOMMENDED CASE DEFINITION
Clinical description
The clinical manifestations of the disease vary in a continuous spectrum between the two polar
forms, lepromateus and tuberculoid leprosy.
In lepromateus leprosy (multibacillary), nodules, papules, macules and diffuse infiltrations are
bilateral symmetrical and usually numerous and extensive; involvement of the nasal mucosa may
lead to crusting, obstructed breathing and epistaxis; ocular involvement leads to iritis and keratitis.
In tuberculoid leprosy (paucibacillary), skin lesions are single or few, sharply demarcated,
anaesthetic or hypesthestic, and bilateral asymmetrical, peripheral nerve involvement tends to be
severe.
Borderline leprosy has features of both polar forms and is more labile.
Indeterminate leprosy is manifested by a hypopigmented maculae with ill-defined borders, and if
untreated, may progress to tuberculoid, borderline or lepromateus disease.
Laboratory criteria for confirmation
Acid-fast bacilli in skin smears (made by the scrape-incision method)
In the paucibacillary form the bacilli may be so few that they are not demonstrable
Case classification
*
WHO operational definition: a person showing clinical signs of leprosy with or without
bacteriological confirmation of the diagnosis and requiring
chemotherapy. (This definition excludes individuals cured of the
infection but having residual disabilities due to leprosy)
Classification (Microbiological).
Paucibacillary (PB). Includes smear-negative indeterminate, tuberculoid and borderline tuberculoid
cases
Multibacillary (MB): Includes ail smear-positive cases
Classification (Clinical):
. Paucibacillary: <= 5 patches or lesions on the skin
Multi bacillary: > 5 patches
RECOMMENDED TYPES OF SURVEILLANCE
Individual patient records at peripheral level for investigation and case-management
Routine monthly reporting of aggregated data of all cases from periphery to intermediate level and
from intermediate to central level.
International: Quarterly and annual reporting of aggregated data from central level to WHO.
RECOMMENDED MINIMUM DATA ELEMENTS
Individual patient records
Unique identifier, name, sex, age, geographical information, disability grade, laboratory
examination, disease classification (MB or PB see case definition), date treatment commenced,
treatment outcome (disability, cured, dropout), contacts
WHO Recommended Surveillance Standards
October 97
65
Aggregated data for reporting
For endemic countries:
• Number of cases by new /old/ disabled
• Number of WHO grade 2 among new cases
• Number of children <=15 years
• Number of multi bacillary patients among new patients
• Number of patients cured with MDT
• Treatment coverage
• Number of patients discharged
Multidrug treatment (MDT) indicators(see special aspects)
MDT supply indicators: For MB adult cases, MB child cases, PB adult cases, PB child cases:
• Number of patients under treatment
• Number of patient months
• Number of Blister Packs used
• Blister Pack Utilisation (%)
RECOMMENDED DATA ANALYSES, PRESENTATION, REPORTS
Point prevalence, annual detection, treatment coverage, number of patients released from registers,
number of cases registered for chemotherapy at the end of the year divided by the population in
which the cases have occurred
Graphs:
Prevalence by year, incidence by year, number of patients on MDT by year, number of
patients cured on MDT by year
Maps:
Number of registered cases, number of new cases, type of treatment, MDT coverage all
by geographical area
Tables:
Prevalence, new case detection, percentage of children, percentage of disabled,
percentage Multi bacillary, number cured with MDT
PRINCIPAL USES OF DATA FOR DECISION MAKING
• Assess the magnitude of the problem,
• Identify variations in case-detection
• Evaluate the policy of elimination of Leprosy
• Plan the distribution of drugs
• Identify technical and operational difficulties faced by the programme
• Identify high risk areas for further targeting intervention
• Evaluate impact of intervention
SPECIAL ASPECTS
•
Leprosy tends to be underreported. Additional reports may come from special projects,
institutions or hospitals. These methods should be used with caution.
•
The use of Multi Drug Treatment (MDT) as a supply indicator may be useful as a surrogate
for prevalence of disease.
CONTACT
Regional offices :
See Regional Communicable Disease contacts on pages 15-20
Headquarters:
Action Programme for the Elimination of Leprosy (LEP)
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: daumerie@who.ch
Tel: (41 22) 791 3919
Fax: (41 22) 791 4850
WHO Recommended Surveillance Standards
October 97
66
Leptospirosis
A27
Leptospirosis
—————————--------Leptospirosis is a zoonosis with a world-wide distribution. It occurs most frequently in countries with
a humid subtropical or tropical climate, often seasonally, often linked to certain occupations,
sometimes in outbreaks. A wide variety of feral and domestic animal species may serve as sources
of infection with one of the many Leptospira serovars. The infection is transmitted to humans by
direct contact with (the urine of) infected animals or a urine-contaminated environment, mainly
surface waters, soil and plants. The course of the disease in humans ranges from mild to lethal.
Leptospirosis is probably overlooked and underreported in many countries due to the difficult clinical
diagnosis and the lack of diagnostic laboratory services. Surveillance provides the basis for
intervention strategies in human or veterinary public health.
RATIONALE FOR SURVEILLANCE
RECOMMENDED CASE DEFINITION
”
----------- —--------Clinical description
An acute febrile illness with headache, myalgia and prostration associated with any of the following
symptoms:
• conjunctival suffusion
• meningeal irritation
• an-Zoliguria and/or proteinuria
• jaundice
• haemorrhages (from the intestines, lung bleeding is notorious in some areas)
• cardiac arrhythmia or failure
• skin rash
and a history of exposure to infected animals or an environment contaminated with animal urine.
Other common symptoms: nausea, vomiting, abdominal pain, diarrhoea, arthralgia
Laboratory criteria for diagnosis
• Isolation (and typing), from blood or other clinical materials by culture of pathogenic leptospires
• Positive serology preferably by the Microscopic Agglutination Test (MAT) using a panel of
Leptospira strains for antigens that, ideally, is representative of the locally occurring strains
Case classification
Suspected:
A case that is compatible with the clinical description
Probable:
Not applicable
Confirmed:
A suspect case that is confirmed in a competent laboratory
Note:
Leptospirosis is difficult to diagnose clinically in areas where diseases with symptoms
similar to those of leptospirosis occur frequently.
RECOMMENDED TYPES OF SURVEILLANCE
Immediate case-based reporting of suspected or confirmed cases from peripheral level (hospital
/general practitioner/laboratory) to intermediate level. All cases should be investigated.
Routine reporting of aggregated data of confirmed cases from intermediate to central level.
International: The International Leptospirosis Society collects world-wide data on occurrence of
leptospirosis
Comment:
Hospital based surveillance may give information on mainly severe cases of leptospirosis.
Serosurveillance may give information on whether leptospiral infections occur or not in
certain areas or populations.
WHO Recommended Surveillance Standards
October 97
67
RECOMMENDED MINIMUM DATA ELEMENTS,
individual patient record for reporting and investigation
Age, sex, geographical information, occupation
Clinical symptoms (morbidity, mortality)
Hospitalisation (Y/N)
History and place of exposure (animal contact, environment)
Microbiological and serological data
Date of diagnosis
Rainfall, flooding
Aggregated data for reporting
Number of cases
Number of hospitalisations
Number of deaths
Number of cases by type (causative serovar/serogroup) of leptospirosis
RECOMMENDED DATA ANALYSES, PRESENTATION, REPORTS
Number of cases by age, sex, occupation, area, date of onset, causative serovars/serogroups,
(presumptive) infection source, transmission conditions (graphs, tables, maps).
Frequency distribution of signs and symptoms by case and causative serovar (tables).
Reports of outbreaks, reports of preventive measures, surveillance of the human
population and populations of feral and domestic animals.
PRINCIPAL USES OF DATA FOR DECISION MAKING:
• Assess the magnitude of the problem in different areas and risk groups/areas/conditions
• Identify outbreaks
• Identify animal sources of infection
• Monitor for emergence of leptospirosis in new areas and new risk (occupational) groups
• Design rational control or prevention methods.
• Identify new serovars and their distribution
• Inform on locally occurring serovars for a representative panel in the MAT
SPECIAL ASPECTS
Serology by MAT may provide presumptive information on causative serogroups.
Attempts should be made at isolation of leptospires and isolates should be typed to assess locally
circulating serovars.
Questioning the patient may provide clues to infection source and transmission conditions.
Animal serology may give presumptive information on serogroup status of the infection;
Isolation followed by typing gives definite information on serovar.
CONTACT
Regional offices
See Regional Communicable Disease contacts on pages 15-20
Headquarters
WHO Division of Emerging and other Communicable Diseases Surveillance and Control (EMC)
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: cosivio@who.ch/ outbreakemc@who.ch
Tel: (41 22) 791 2531 / 4687 / 2111
Fax: (41 22) 791 4893 / 0746 attn EMC
WHO Recommended Surveillance Standards
October 97
68
Malaria
B50-54
Malaria
RATIONALE FOR SURVEILLANCE
Malaria is the first most prevalent tropical disease with a high morbidity and mortality and high
economical and social impact. The Global Strategy for Malaria Control is mentioned in the 9GPW.
Its elements include: to provide early diagnosis and treatment; to plan and implement selective and
sustainable preventive measures, including vector control; to detect early, contain and prevent
epidemics. Therefore surveillance is essential.
RECOMMENDED CASE DEFINITION
applies to endemic areas and to people exposed to malaria (e.g., history of visit to endemic area)
In all countries malaria must primarily be defined in association with clinical disease symptoms. The
: case definition for malaria cannot be uniform throughout the world: it will vary according to how
malaria is perceived in a given country, local patterns of transmission, and disease consequences.
Each national malaria control programme must adapt the definition and introduce additional
indicators to make it more applicable to local epidemiology and control targets. The suggested case
definitions are deliberately broad.
Clinical description
Signs and symptoms vary, most patients experience fever. Common associated symptoms include
headache, back pain, chills, sweats, myalgia, nausea, vomiting, diarrhoea, and cough. Untreated
Plasmodium falciparum infection can lead to coma, generalised convulsions, hyperparasitaemia,
normocytic anaemia, fluid, electrolyte, and acid-base disturbances, renal failure, hypoglycaemia,
hyperpyrexia, malarial haemoglobinuria, circulatory collapse and shock, spontaneous bleeding
(disseminated intravascular coagulation), pulmonary oedema, and death.
>
Laboratory criteria for diagnosis
Demonstration of malaria parasites in blood films
Case classification
uncomplicated malaria. A person showing signs and symptoms of malaria, with or without
microscopic confirmation, who requires antimalarial treatment.
severe malaria: A patient who requires hospitalisation for a febrile disease and is treated for severe
malaria. The diagnosis should preferably be confirmed microscopically.
Some Health Services (HS) record malaria patients as “suspected malaria” until the microscopic
diagnosis is available, after which the patient becomes “confirmed malaria”. These HS should take
care to avoid double counting, and record the confirmed cases as a subset of the suspected cases.
suspected malaria death: Death of a patient suffering from suspected severe malaria (/.e., without
microscopic confirmation)
confirmed malaria death: Death of a patient suffering from microscopically confirmed severe
malaria
“Suspected malaria death" and “confirmed malaria death” are mutually exclusive categories.
malaria treatment failure: A patient with uncomplicated malaria without any clear symptoms
suggesting another concomitant disease who has taken a correct dosage
of antimalarial treatment, and who presents with clinical deterioration or
recurrence of symptoms within 14 days of the start of treatment, in
combination with an asexual parasitaemia
WHO Recommended Surveillance Standards
October 97
69
RECOMMENDED TYPES OF SURVEILLANCE
------------------------- ------------------------- n
• Routine monthly reporting of aggregated data of uncomplicated malaria severe malaria
suspected and confirmed malaria deaths, treatment failures from peripheral level to intermediate
and central level.
• Surveys built into the supervision and retraining process. Topics include the availability and use
of anti-malarial drugs. Every three months aggregated data are forwarded from the peripheral
level to the intermediate and central level.
• Special surveys and “sentinel site" monitoring. Topics include drug utilisation studies of malaria
cases treated at home and in the private sector; assessment of therapeutic efficacy of
antimalarial drugs; estimating malaria-associated deaths in the community
• Timely recognition of malaria epidemic and notification at all times.
Note:
The primary purpose of surveillance is to guide malaria control activities at the level where
data are collected. In addition, regularly completed forms provide an important numeric
picture of trends in malaria incidence and mortality in the various units that diagnose and
treat malaria.
RECOMMENDED MINIMUM DATA ELEMENTS
"
“
Note: According to epidemiological circumstances, different segments of the population may
be affected by malaria. Knowledge of the age groups, sex and pregnancy status of patients
is vital information. All malaria data should be reported by age group (A) and sex (S), with a
separate category for pregnant women (P)
Case-based data:
From peripheral level without microscopy
• uncomplicated malaria: A/S/P
• severe malaria: A/S/P, referral (Y/N)
• suspected malaria death: A/S/P
• presumptive malaria treatment failure A/S/P, treatment taken
‘patients who do not respond to a full treatment with the first line drug and therefore need an
alternative antimalarial drug
From peripheral level with laboratory facility same as peripheral level without microscopy plus
• type of malaria (falciparum, ovale, malariae, vivax)
• confirmed malaria death: A/S/P
Aggregated data for reporting
From peripheral level without laboratory facility:
• number of cases of uncomplicated malaria, severe malaria, malaria treatment failures(by
treatment taken), by A/S/P,
• suspected malaria mortality, by A/S/P
From peripheral level with laboratory facility same as peripheral level without microscopy plus
• type of malaria
• confirmed malaria mortality by A/S/P
WHO Recommended Surveillance Standards
October 97
70
Malaria
B50-54
Malaria
RATIONALE FOR SURVEILLANCE
Malaria is the first most prevalent tropical disease with a high morbidity and mortality and high
economical and social impact. The Global Strategy for Malaria Control is mentioned in the 9GPW.
Its elements include: to provide early diagnosis and treatment; to plan and implement selective and
sustainable preventive measures, including vector control; to detect early, contain and prevent
epidemics. Therefore surveillance is essential.
RECOMMENDED CASE DEFINITION
applies to endemic areas and to people exposed to malaria (e.g., history of visit to endemic area)
In all countries malaria must primarily be defined in association with clinical disease symptoms. The
case definition for malaria cannot be uniform throughout the world: it will vary according to how
malaria is perceived in a given country, local patterns of transmission, and disease consequences.
Each national malaria control programme must adapt the definition and introduce additional
indicators to make it more applicable to local epidemiology and control targets. The suggested case
definitions are deliberately broad.
Clinical description
Signs and symptoms vary, most patients experience fever. Common associated symptoms include
headache, back pain, chills, sweats, myalgia, nausea, vomiting, diarrhoea, and cough. Untreated
Plasmodium falciparum infection can lead to coma, generalised convulsions, hyperparasitaemia,
normocytic anaemia, fluid, electrolyte, and acid-base disturbances, renal failure, hypoglycaemia,
hyperpyrexia, malarial haemoglobinuria, circulatory collapse and shock, spontaneous bleeding
(disseminated intravascular coagulation), pulmonary oedema, and death.
Laboratory criteria for diagnosis
Demonstration of malaria parasites in blood films
Case classification
uncomplicated malaria: A person showing signs and symptoms of malaria, with or without
microscopic confirmation, who requires antimalarial treatment.
severe malaria: A patient who requires hospitalisation for a febrile disease and is treated for severe
malaria. The diagnosis should preferably be confirmed microscopically.
Some Health Services (HS) record malaria patients as “suspected malaria" until the microscopic
diagnosis is available, after which the patient becomes “confirmed malaria". These HS should take
care to avoid double counting, and record the confirmed cases as a subset of the suspected cases.
suspected malaria death'. Death of a patient suffering from suspected severe malaria (/.e., without
microscopic confirmation)
confirmed malaria death: Death of a patient suffering from microscopically confirmed severe
malaria
“Suspected malaria death" and “confirmed malaria death" are mutually exclusive categories.
malaria treatment failure: A patient with uncomplicated malaria without any clear symptoms
suggesting another concomitant disease who has taken a correct dosage
of antimalarial treatment, and who presents with clinical deterioration or
recurrence of symptoms within 14 days of the start of treatment, in
combination with an asexual parasitaemia
WHO Recommended Surveillance Standards
October 97
69
RECOMMENDED TYPES OF SURVEILLANCE
“
------------------• Routine monthly reporting of aggregated data of uncomplicated malaria, severe malaria,
suspected and confirmed malaria deaths, treatment failures from peripheral level to intermediate
and central level.
• Surveys built into the supervision and retraining process. Topics include the availability and use
of anti-malarial drugs. Every three months aggregated data are forwarded from the peripheral
level to the intermediate and central level.
• Special surveys and “sentinel site" monitoring. Topics include drug utilisation studies of malaria
cases treated at home and in the private sector; assessment of therapeutic efficacy of
antimalarial drugs; estimating malaria-associated deaths in the community
• Timely recognition of malaria epidemic and notification at all times.
Note:
The primary purpose of surveillance is to guide malaria control activities at the level where
data are collected. In addition, regularly completed forms provide an important numeric
picture of trends in malaria incidence and mortality in the various units that diagnose and
treat malaria.
RECOMMENDED MINIMUM DATA ELEMENTS
Note: According to epidemiological circumstances, different segments of the population may
be affected by malaria. Knowledge of the age groups, sex and pregnancy status of patients
is vital information. All malaria data should be reported by age group (A) and sex (S), with a
separate category for pregnant women (P)
Case-based data:
From peripheral level without microscopy
• uncomplicated malaria: A/S/P
• severe malaria: A/S/P, referral (Y/N)
• suspected malaria death: A/S/P
• presumptive malaria treatment failure A/S/P, treatment taken
‘patients who do not respond to a full treatment with the first line drug and therefore need an
alternative antimalarial drug
From peripheral level with laboratory facility same as peripheral level without microscopy plus
• type of malaria (falciparum, ovale, malariae, vivax)
• confirmed malaria death: A/S/P
Aggregated data for reporting
From peripheral level without laboratory facility:
• number of cases of uncomplicated malaria, severe malaria, malaria treatment failures(by
treatment taken), by A/S/P,
• suspected malaria mortality, by A/S/P
From peripheral level with laboratory facility same as peripheral level without microscopy plus
• type of malaria
• confirmed malaria mortality by A/S/P
WHO Recommended Surveillance Standards
October 97
70
RECOMMENDED DATA ANALYSES, PRESENTATION, REPORTS
Disease trends and patterns are the principal concern of malaria control programmes.
Reports:
Monthly reports of aggregated data to the next level, by geographical area (district)
Graphs.
Time trends for the different geographical areas. An elevation of cases over two
standard deviations as compared to averaged data from previous “normal” years of
transmission may indicate an epidemic
Maps:
Presence/absence of malaria cases; reporting completeness and timeliness
Line list
Peripheral and intermediate levels that sent no monthly report or untimely reports
PRINCIPAL USES OF DATA FOR DECISION MAKING
• Identify high risk groups and problem areas (e.g., districts where therapeutic efficacy studies
must urgently be carried out)
• Evaluate impact of control measures
• Adjust and target control measures
• Guide allocation of resources and training efforts
SPECIAL ASPECTS
Many cases may be treated at home or by private practitioners. It is a challenge for malaria control
to incorporate home treatment and private practitioners in surveillance and control.
CONTACT
Regional offices
Regional Malaria Adviser AFRO fax 1-407-953 94 00, tel. 1-407-953 91 11
Regional Malaria Adviser AMRO fax 1-202-974 36 63, tel. 1-202-974 30 00
Regional Malaria Adviser EMRO fax 20-3-483 89 16, tel. 20-3-482 02 23
Regional Malaria Adviser SEARO fax 91-11 -33T 86 07, tel. 91-11-331 78 04
Regional Malaria Adviser WPRO fax 63-2-521 10 36, tel. 63-2-521 84 21
Malaria Adviser EURO c/o Malaria Unit, CTD/MAL, WHO Geneva (see below)
Headquarters
WHO Division of Control of Tropical Diseases (CTD), Malaria Control (MAL),
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: rietvelda@who.ch
Tel: (41 22) 791 3753/2111
Fax: (41 22) 791 0000 attn MAL
WHO Recommended Surveillance Standards
October 97
71
Measles
BOS
Measles
RATIONALE FOR SURVEILLANCE
Measles is targeted for elimination (9GPW 6.2). Surveillance for measles should evolve with each
phase of measles control. Countries in the “measles control" phase are endemic and should
concentrate on raising routine measles immunization coverage and focusing extra immunization
efforts in areas with high measles morbidity. Countries in the more advanced "measles outbreak
prevention phase" are achieving high routine measles coverage and low incidence with periodic
outbreaks. Surveillance in these countries should be used to predict potential outbreaks and identify
risk outbreak. Countries in the most advanced “measles elimination phase" in which the objective is
to completely interrupt measles transmission require very intensive case-based surveillance to
detect, investigate, and confirm every suspect measles case in the community.
RECOMMENDED CASE DEFINITION
Clinical case definition
Any person with:
• fever, and
• maculopapular (i.e. non-vesicular) rash, and
• cough, coryza (i.e. runny nose) or conjunctivitis (i.e. red eyes).
or
Any person in whom a clinician suspects measles infection
Laboratory criteria for diagnosis
• At least a four-fold increase in antibody titre or isolation of measles virus or
• Presence of measles-specific IgM antibodies
r
Case classification
Clinically confirmed: A case that meets the clinical case definition
Probable:
Not applicable
Laboratory-confirmed A case that meets the clinical case definition and that is laboratory
confirmed or linked epidemiological to a laboratory-confirmed case
RECOMMENDED TYPE(S) OF SURVEILLANCE
Control phase: When measles is endemic, routine monthly reporting of aggregated data of clinical
cases from peripheral to intermediate and central level. Only outbreaks (not each case)
should be investigated.
International: routine monthly reporting of aggregated data specifying geographical area
and month of onset from central level to WHO regional offices.
Outbreak prevention phase: When low incidence is achieved with periodic outbreaks due to
accumulation of susceptibles, routine monthly reporting of aggregated data of clinical cases
from peripheral to intermediate and central level. All suspected outbreaks should be
investigated immediately and case-based data collected. Suspected epidemics should be
confirmed by conducting serology on the first few cases only.
International: routine monthly reporting of aggregated data of clinical cases specifying
geographical area, month of onset, age group and immunization status
Elimination phase: Case-based surveillance should be conducted and every case reported and
investigated immediately from peripheral level to intermediate level, and also included in the
weekly reporting system. Laboratory specimens should be collected on every case.
WHO Recommended Surveillance Standards
October 97
73
RECOMMENDED MINIMUM DATA ELEMENTS
Control phase (aggregated data):
• Number of cases
• Number of measles vaccine doses administered to infants
Outbreak prevention phase ((aggregated data): Same as control phase, plus
• Cases by age group and immunization status
Elimination phase (case-based data):
• Unique identifier, geographical area, date of birth
• Date of rash onset, notification, case investigation, specimen collection
• Number of measles vaccine doses received
• Source of infection identified (yes/no/unknown)
• Results of serology (positive/negative/no specimens processed/unknown)
• Final classification (clinically confirmed/confirmed by laboratory/confirmed by epi
lin k/discarded)
In every phase: completeness/timeliness of weekly measles reporting must be monitored
RECOMMENDED DATA ANALYSES, PRESENTATION, REPORTS
For control phase
• Incidence rate by month, year, and geographic area
• Measles vaccine coverage by year and geographic area
• Completeness/timeliness of monthly reporting
• Proportional morbidity (compared to other diseases of public health importance)
For outbreak prevention phase: same as control phase plus the following:
• Age-specific incidence rate
• Cases by age group and immunization status
For measles elimination: same as outbreak prevention phase plus the following:
Target
Performance indicators
80%
% of weekly reports received
80%
% of cases* notified < 7 days of rash onset
80%
% of cases* investigated < 48 hours of notification
80%
% of cases* with adequate specimen**and lab results
80%
% of confirmed cases with source of infection identified
* all cases that meet the clinical case definition
** adequate specimen is one blood specimen collected within 3-28 days of rash onset
PRINCIPAL USES OF DATA FOR DECISION-MAKING
Control phase: Monitor incidence and coverage to monitor progress (decreasing incidence and
increasing coverage), and to identify areas at high risk or with poor performance.
Outbreak prevention phase: Describe the changing epidemiology of measles in terms of age and
inter-epidemic period. Identify high-risk populations. Determine when the next outbreak
may occur due to a build-up of susceptibles and accelerate activities beforehand.
Elimination phase: Determine where measles virus is circulating or may circulate (i.e. high risk)
and the performance of the surveillance system (e.g. reaction time for notification, and
specimen collection) to detect virus circulation or potential importation.
During any phase: Detect and investigate outbreaks to ensure proper case management.
Determine why the outbreak occurred (failure to vaccinate, vaccine failure, accumulation
of susceptibles).
WHO Recommended Surveillance Standards
October 97
74
SPECIAL ASPECTS REQUIRING EXPLANATION
Final classification of measles cases (elimination phase)
Adequate
s p e e im e n
Ij.M
n e t a tiv e
I g M
positive
D istird
blood
Laboratory
confirm ed
Suspect
m e a S Ie s
N o adequate blood
specimen
N o epidem iologic link
laboratory confirm ed
C lin ic a 11 y
confirm ed
CONTACT
Regional offices
See Regional Communicable Disease contacts on pages 15-20
Headquarters
Expanded Programme on Immunization (EPI)
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: olivejm@who.ch
Tel: (41 22) 791 4408/4409/2111
Fax: (41 22) 791 4193 attn EPI
)
WHO Recommended Surveillance Standards
October 97
75
Meningococcal disease
A39
Meningococcal disease
(Meningococcal infection A39
Meningococcal meningitis A39.0; Meningococcemia A39.4)
RATIONALE FOR SURVEILLANCE
Meningococcal disease occurs sporadically and in epidemics of meningococcal meningitis- the
majority of cases in children under 5 years. Meningococcal meningitis is the only form of meningitis
to cause epidemics. Case fatality is between 5%-15%. While sub-Saharan Africa is most affected,
epidemic meningococcal disease can affect any country. Vaccines are available for two serogroups
only, A and C, and should be considered in entire populations. WHO policy is control and
containment of epidemics, early warning of and appropriate response to outbreaks. Surveillance is
needed to measure and detect epidemics and establish the impact of both epidemic and non
epidemic disease.
RECOMMENDED CASE DEFINITION
Clinical case definition
An illness with sudden onset of fever (>38.5 °C rectal or 38.0 °C axillary)
and one of the following
• neck stiffness
• altered consciousness
• other meningeal sign
or petechial or purpural rash
In patients <1 year of age meningitis is suspected when fever is accompanied by a bulging
fontanelle
Laboratory criteria for diagnosis
positive CSF antigen detection or positive culture
Case classification
Suspected:
A case that meets the clinical case definition.
Probable:
A suspected case as defined above:
turbid CSF (with or without positive Gram stain)
and
ongoing epidemic and epidemiological link to a confirmed case
or
A suspected or probable case with laboratory confirmation.
Confirmed
RECOMMENDED TYPES OF SURVEILLANCE
At peripheral level individual patient records should be maintained (particularly because of contact
tracing).
Immediate reporting of all suspected or probable cases from peripheral level to intermediate level.
All cases should be investigated. Follow-up data on organism identified and patient outcome should
be sought by the intermediate level.
Routine weekly/monthly reporting of aggregated or case-based data from intermediate to central
level.
A parallel surveillance using reference laboratories for meningococcal diseases may provide
detailed microbiological data on serogroup and genotype on a central basis; These are very useful
for epidemiological analysis.
WHO Recommended Surveillance Standards
October 97
77
Note 1: In countries with poor surveillance infrastructure two approaches to clinical surveillance can
be integrated. A limited amount of data can be reported from all health sites (e.g. new
cases and deaths by week), more extensive data can be reported from selected referral
health centres.
Note 2: Surveillance of vaccine coverage may be undertaken in areas of mass vaccination or where
vaccination for meningococcal disease is part of routine vaccination.
RECOMMENDED MINIMUM DATA ELEMENTS
CLINICAL SURVEILLANCE:
Case-based data for individual patient records and for reporting.
Case classification (suspected/probable/confirmed), unique identifier, age, sex, geographical
information, date of onset, date of consultation, vaccination status, treatment received, history of
contact with a case, close contacts
Aggregated data for reporting:
Cases by case classification (suspected/probable/confirmed), age group, week, geographical
area, and outcome
LABORATORY SURVEILLANCE
Isoiate-based data for reporting:
Unique identifier, age, sex, date of onset, date of specimen, specimen type, serogroup
genotype
Aggregated data for reporting:
Cases by agegroup, specimentype, serogroup, genotype
RECOMMENDED DATA ANALYSES, PRESENTATION, REPORTS
• Incidence by week, month, geographical area and age group
• Use of incidence data to set epidemic thresholds by comparison of weekly incidence rate and the
incidence rates during the same period in 3-5 previous non-epidemic years.
• Incidence by serogroup and genotype (if available) •
• Vaccine coverage (if available)
PRINCIPAL USES OF DATA FOR DECISION MAKING
• Detect and control epidemics of meningococcal disease as early as possible, especially in areas
such as developing countries where epidemic meningitis raises particular difficulties
• Strengthen the capacity for emergency response to epidemics of meningococcal disease.
• Mobilise immunization activities
• Monitor immunization coverage by geographical area to monitor progress and identify areas of
poor performance
• Monitor impact of vaccination on disease incidence and vaccine efficacy during epidemics
SPECIAL ASPECTS
Deciding when an epidemic is occurring
In hyoerendemic areas: 15 cases per 100 000 per week averaged over 2 consecutive weeks Once
epidemic disease is detected in a given area a lower value (e.g., 5 cases/100 000 per week ) should
be used as a threshold in contiguous areas.
In other situations; a 3 to 4-fold increase in cases compared with a similar time period in previous
years, or a doubling of cases from one week to the next for a period of 3 weeks.
CONTACT
Regional offices
See Regional Communicable Disease contacts on pages 15-20
Headquarters
WHO Division of Emerging and other Communicable Diseases Surveillance and control (EMC)
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: tikhomirove@who.ch / outbreakemc@who.ch
Tel: (41 22) 791 2656 / 2850 / 2111
Fax: (41 22) 791 4878 / 0746 attn EMC___________
WHO Recommended Surveillance Standards
October 97
78
Viral meningitis
A87
Viral meningitis
RATIONALE FOR SURVEILLANCE
Viral meningitis occurs sporadically and also as epidemic disease. While mortality rates are
generally low, infection can cause high levels of morbidity and potential long term sequelae in those
affected (mostly children). The early detection of epidemics through epidemiological surveillance
allows for identification of the causal agent and the institution of targeted control measures and
effective case management.
RECOMMENDED CASE DEFINITION:
Clinical case definition
A case with fever >=38°C and one or more of the following:
• neck stiffness
• severe unexplained headache
• neck pain and two or more of the following: photophobia
nausea
vomiting
abdominal pain
pharyngitis with exudates
For children less than two years of age a case is defined as a case with fever>=38.3°C
and one or more of the following.
• irritability
• bulging fontanelle
Laboratory criteria for confirmation
The specific virus confirmed on cell culture
Case classification
Suspected:
A case that meets the clinical case definition
Probable:
A suspected case with one or more of the following
• Normal CSF glucose and normal or mild increase in CSF protein
(>50mg/dl), moderate increase CSF cells (<500/mm3) and lymphocyte
predominance (>50%)
• CSF Positive for viral genomic sequences using PCR (Polymerase Chain
Reaction)
• Epidemiological link to a confirmed case
A suspected or probable case with laboratory confirmation
Confirmed:
RECOMMENDED TYPES OF SURVEILLANCE
At peripheral level individual patient records should be maintained.
Immediate reporting of all suspected or probable cases from peripheral level to intermediate level
and central level.
All cases should be investigated. Follow-up data on organism identified and patient outcome should
be sought by the intermediate and central level.
Routine weekly reporting of aggregated or case-based data from intermediate to central level.
A parallel surveillance using reference laboratories for viral diseases may provide more detailed
virological data on specific causal agents on a national basis which are very useful for
epidemiological analysis.
WHO Recommended Surveillance Standards
October 97
79
RECOMMENDED MINIMUM DATA ELEMENTS
““
CLINICAL SURVEILLANCE:
Case-based data for individual patient record and for reporting.
Case classification (suspect/probable/confirmed), unique identifier, age, sex, geographical
information, date of onset, date of consultation, treatment received
Aggregated data for reporting.
Cases by case classification (suspect/probable/confirmed), age group, week, geographical area,
and outcome
LABORATORY SURVEILLANCE
Isolate-based data for reporting:
Unique identifier, age, sex, date of onset, date of specimen, specimen type, organism identified
Aggregated data for reporting:
Cases by agegroup, specimen type, organism identified
RECOMMENDED DATA ANALYSES, PRESENTATION, REPORTS
Incidence by week, month, geographical area, age group, outcome.
PRINCIPAL USES OF DATA FOR DECISION MAKING
• To detect and control epidemics of viral meningitis as early as possible
• To strengthen the capacity for emergency response to epidemics of viral meningitis
SPECIAL ASPECTS:
None
CONTACT
Regional offices
See Regional Communicable Disease contacts on pages 15-20
Headquarters
WHO Division of Emerging and other Communicable Diseases Surveillance and Control (EMC)
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: tikhomirove@who.ch / outbreakemc@who.ch
Tel: (41 22) 791 2656 / 2850 / 2111
Fax: (41 22) 791 4878 / 0746 attn EMC
WHO Recommended Surveillance Standards
October 97
80
Neonatal tetanus
A33
Neonatal tetanus
RATIONALE FOR SURVEILLANCE
Targeted by WHO for elimination (9GPW). High tetanus toxoid (TT) coverage of pregnant-women,
clean delivery, identification, and implementation of corrective action in high risk areas
(i.e. immunization of childbearing-age women) are the three primary strategies towards this goal.
Epidemiological surveillance is particularly useful in the identification of high risk areas and to
monitor impact of interventions.
RECOMMENDED CASE DEFINITION
Clinical case definition and case classification
Suspected case: Any neonatal death between 3-28 days of age in which the cause of death is
unknown; or any neonate reported as having suffered from neonatal tetanus
between 3-28 days of age and not investigated.
Confirmed case: Any neonate with a normal ability to suck and cry during the first two days of
life, and who between 3 and 28 days of age cannot suck normally, and
becomes stiff or has convulsions (i.e. jerking of the muscles) or both.
(Hospital reported NT cases are considered confirmed)
The diagnosis is entirely clinical and does not depend upon bacteriological confirmation.
RECOMMENDED TYPES OF SURVEILLANCE
The number of confirmed NT cases should be included in routine monthly surveillance reports of all
countries and should be reported as a separate item from other (non-neonatal) tetanus. Zero
reporting should be required at all levels.
Active surveillance in major health facilities on a regular basis (at least once annually).
In “low risk" geographical areas (i.e. NT incidences/1000 live births and surveillance is functional),
all suspect cases should be investigated to confirm and identify tfie cause.
Community surveillance in “silent" areas (i.e. where routine reporting is not functional but where,
based on other indicators, neonatal tetanus could be a problem).
RECOMMENDED MINIMUM DATA ELEMENTS
Aggregate data for reporting
• Number of cases
• Doses of TT administered to pregnant or child-bearing aged women (depending on national
policy) or % of newborns protected at birth (PAB)
• Completeness / timeliness of monthly reports
Case-based data, individual patient records for investigation
• Unique identifier, geographical information, date of birth, age (in days) at onset, sex of baby
• Parity (number of deliveries including the current delivery or pregnancy)
• Date of case investigation
• Location/type of birth (institution, home with trained attendant, home with untrained attendant,
home without attendant, other)
• Tetanus immunization status of mother when she gave birth (up-to-date, not up-to-date,
unimmunized)
• Final classification (confirmed, suspected, discarded)
• Mother of case given subsequent protective TT dose within 3 months of report
• Supplemental immunization conducted within same locality as the case
WHO Recommended Surveillance Standards
October 97
81
RECOM MENDED DATA ANALYSES, PRESENTATION, REPORTS
For aggregated data(i.e. routine monthly reporting)
• Incidence rate per 1000 live births by geographic area, month, and year
• TT2+ (or PAB) by year and geographic area
• Completeness/timeliness of monthly reporting
• Geographic areas considered at high risk for NT compared to those where corrective actions
were taken
For case based data (i.e. from case investigations only) same as for aggregate data plus the
following:
• Confirmed NT cases by delivery type, sex, TT2+ status of the mother
• % of confirmed cases for which the mother subsequently received a protective TT dose
PRINCIPAL USES OF DATA FOR DECISION-MAKING/ACTION
• Monitor progress towards achieving and sustaining high routine TT2+(or PAB) coverage in all
geographical areas
• Monitor progress towards eliminating NT in every geographical area
• Investigate suspect NT cases in areas not considered at risk for NT to confirm and determine
cause
• Identify high risk geographical areas and conduct 3 rounds of supplemental TT immunization in
those high risk geographical areas
• Periodically validate sensitivity of NT reporting by comparing number of reported cases with
cases identified through active surveillance
SPECIAL ASPECTS
---------------------------- - -----------------“% Protected at birth (PAB)" is an alternative method of determining coverage (particularly where
TT2+ is unreliable). To monitor PAB, health workers record during DTP1 visits whether the infant
was protected at birth by the mother's TT status and/or delivery status(clean/unclean). % PAB is
then estimated as: number of infants protected/number of live births. If the child was unprotected,
the mother should receive a dose of tetanus toxoid during the same visit and should be followed up
with a subsequent TT dose if needed for protection.
CONTACT
Regional offices
*
See Regional Communicable Disease contacts on pages 15-20
Headquarters
Expanded Programme on Immunization (EPI)
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: gassef@who.ch
Tel: (41 22) 791 4414/4409/2111
Fax: 791 4193 attn EPI
WHO Recommended Surveillance Standards
October 97
82
Onchocerciasis
873
Onchocerciasis
(River-blindness)
RATIONALE FOR SURVEILLANCE
Onchocerciasis is endemic in 34 countries of Africa, the Arabian peninsula and the Americas.
Outstanding success at controlling the disease in West Africa was achieved through the strategy of
larviciding for vector control to interrupt transmission. The development of a safe, effective drug,
ivermectin, has let to a new global strategy for controlling onchocerciasis based on yearly
administration of ivermectin to affected populations. The first step is to map the endemicity of
onchocerciasis in known or potentially endemic areas. The second step is to develop cost-effective
an sustainable methods for ivermectin delivery, focusing on methods involving community
treatment. Once onchocerciasis is under control, the risk of recrudescence has to be reduced to a
minimum. Therefore the participating countries, during the phasing-out period 1998-2002 in west
Africa, will ensure that the detection and control of recrudescence of onchocerciasis are routinely
integrated within and have become a routine function of the national multi-disease surveillance and
control services.
RECOMMENDED CASE DEFINITION
Clinical case definition
In an endemic area, a person with fibrous nodules in subcutaneous tissues
Laboratory criteria for confirmation
one or more of the following
• Presence of microfilariae in skin snips taken from the iliac crest
• Presence of adult worms in excised nodules
• Presence of typical ocular manifestations, slit-lamp observations of microfilariae in the cornea
anterior chamber or vitreous body
Case classification
Suspected:
A case that meets the clinical case definition
Probable:
Not applicable
Confirmed:
A suspected case that is laboratory-confirmed
RECOMMENDED TYPES OF SURVEILLANCE
In the onchocerciasis-freed zones:
Surveillance in sentinel villages:
To detect recrudescence of infection, 260 villages in onchocerciasis-freed zones have been
maintained under periodic surveillance (every 3 years). They are sentinel villages located near
former productive larval breeding sites and with high prevalence rates prior to beginning of control
activities.
Routine surveillance:
All suspected cases should be investigated locally and routine reporting of aggregated data from
peripheral level to intermediate and central level. This is not yet fully effective in all of the countries
due to insufficient training of health workers. Migration investigation: In the event that a positive
case is detected during the epidemiological surveillance a migration investigation is systematically
carried out in order to identify the origin of infection and take appropriate action.
In the onchocerciasis endemic zones:
Active case finding (skin snips, ophthalmologic examination, DEC patch test) through sun/eys.
Distribution of the disease can be assessed through rapid epidemiological mapping (REMO)
technique recently developed.
WHO Recommended Surveillance Standards
October 97
83
RECOMMENDED MINIMUM DATA ELEMENTS
'
Individual patient record at peripheral level.
Age, sex, place of infection, treatment (Y/N), date treatment with Ivermectin commenced, reason
of non treatment (non compliance)
Aggregated data for reporting:
Prevalence and incidence by age, sex and geographical area
Number of cases treated
Number of cases not treated because of pregnancy, breast feeding, defaulter
RECOMMENDED DATA ANALYSES, PRESENTATION, REPORTS
Graphs: Number of cases by year, geographical area, age group
Tables: Number of cases by year, geographical area, age group
Maps: Number of cases by geographical area, use of geographical information system (GIS)
PRINCIPAL USES OF DATA FOR DECISION MAKING
• Elimination of onchocerciasis as a disease of public health and socio-economic importance
• Prevention of recrudescence of infection in the onchocerciasis-freed zones
• Assess effectiveness of intervention.
SPECIAL ASPECTS
New diagnostic tests, such as DEC (Di-ethylcarbamazine citrate) patch tests may become suitable
for use in the field
CONTACT
Regional offices
See Regional Communicable Disease contacts on pages 15-20
headquarters
Onchocerciasis Control Programme (OCR)
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: daribia@who.ch
Tel: (41 22) 791 3883/2111
Fax: (41 22) 791 4190 attn OCR
WHO Recommended Surveillance S rand a rd s
October 97
84
Pertussis
A37.0
Pertussis
(Whooping cough)
RATIONALE FOR SURVEILLANCE
Pertussis is a major cause of childhood morbidity and mortality. Every year nearly 5 million children
suffer from broncho-pneumonia as a result of pertussis infection and 50 000 develop long-term
neurological sequelae. Case fatality in developing countries can reach 15%. High routine coverage
with effective vaccine is the mainstay of prevention. Surveillance data on the disease can monitor
the impact of vaccination on disease incidence and identify high risk areas.
RECOMMENDED CASE DEFINITION
Clinical case definition
A person with a cough lasting at least 2 weeks with one of the following
. paroxysms (i.e. fits) of coughing,
. inspiratory “whoop",
. post-tussive vomiting (i.e. vomiting immediately after coughing),
and without other apparent cause.
Laboratory criteria for diagnosis
. isolation of Bordeteila pertussis, or
. presence of IgG or IgA directed toward pertussis toxin (PT) or filamentous hemagglutinin
antigen (FHA).
Case classification
A case that meets the clinical case definition
Suspected:
A suspected case that is laboratory-confirmed or linked epidemiological to a
Confirmed:
laboratory-confirmed case
RECOMMENDED TYPES OF SURVEILLANCE
Routine monthly reporting of aggregated data of suspected and confirmed cases from peripheral
level to intermediate and central level. All outbreaks should be investigated immediately and
laboratory-confirmed. During an outbreak, case-based data should be collected
Case-based surveillance may be considered in countries with low pertussis incidence (usually
where coverage is >80%).
International: Aggregated data of clinical (suspected)l and confirmed cases should be included in
routine monthly surveillance reports of all countries to WHO regional offices.
RECOMMENDED MINIMUM DATA ELEMENTS
Aggregated data for reporting
Number of cases
Number of third doses of diphteria-pertussis-tetanus vaccine (DTP3) administered to infants
Completeness/timeliness of monthly reports
Case-based data for investigation and reporting
Unique identifier, geographical information, date of birth, date of onset, total pertussis vaccine
doses, classification (confirmed/suspected/discarded), outcome (alive/dead/unknown)
WHO Recommended Surveillance Standards
October 97
85
RECOMMENDED DATA ANALYSES, PRESENTATION, REPORTS
Aggregated data
• Incidence rate by month, year, and geographic area
• DTP3 coverage by year and geographic area
• Completeness/timeliness of monthly reporting
• Proportional morbidity (compared to other diseases of public health importance)
Case-based data same as aggregated data plus the following:
• Age-specific incidence rate
• Immunization status of cases
• Case fatality rate
PRINCIPAL USES OF DATA FOR DECISION MAKING
• Investigate outbreaks to understand epidemiology qf pertussis in the country, why the outbreak
occurred (e.g. failure to immunise, vaccine failure, accumulation of susceptibles/waning
immunity), and to ensure proper case management
• Monitor case fatality rate. If high, determine cause (e.g. poor case management, lack of
antibiotics/supportive care, patients not seeking treatment in time)
• Determine age-specific incidence rate, and incidence rate by geographical area to know risk
groups
• Monitor incidence rate to assess impact of control efforts
CONTACT
Regional offices
See Regional Communicable Disease contacts on pages 15-20
Headquarters
Expanded Programme on Immunization (EPI)
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: melgaardb@who.ch
Tel: (41 22) 791 4409/2111
Fax: 791 4193 attn EPI
WHO Recommended Surveillance Standards
October 97
86
Plague
A20
Plague
(human)
Case report universally required by International Health Regulations
RATIONALE FOR SURVEILLANCE
Disease endemic in many countries and often has epidemic potential. Surveillance of human and
animal disease is important to predict and detect epidemics and to monitor control measures. Case
report universally required by International Health Regulations.
RECOMMENDED CASE DEFINITION
Clinical description
Plague is transmitted to humans by fleas or by direct exposure to infected tissues or respiratory
droplets. The disease is characterised by
Rapid onset of fever, chills, headache, severe malaise, prostration with
for Bubonic form: extreme painful swelling of lymph nodes (buboes)
for Pneumonic form: cough with blood -stained sputum, chest pain, difficult breathing
Laboratory criteria for diagnosis
. Cultural isolation of Yersinia pestis from buboes, blood, CSF or sputum or
. Passive hemagglutination test (PHA test) demonstrating four fold change in antibody titre,
specific for F1 antigen of Y. pestis (HI test) in paired sera
Case classification
A case compatible with the clinical description
Suspected:
May or may not be supported by laboratory finding of Gram stain negative bipolar
coccobaccili in clinical material (bubo aspirate, sputum, tissue, blood)
Probable:
A suspected case with
• Positive FA test for Y. pestis in clinical specimen or
• PHA test, with antibody titre of >= 1:10, specific for the F1 antigen of Y.pestis
as determined by HI.
or
• Epidemiological link with a confirmed case.
A suspected or probable case that is laboratory-confirmed
Confirmed:
RECOMMENDED TYPES OF SURVEILLANCE
In all situations: Immediate case-based reporting of suspected cases from peripheral level to
intermediate and central level. Laboratory based reporting of all confirmed cases should
pertain in all situations
During an outbreak: Intensified surveillance: active case finding and contact tracing should be
undertaken in order that treatment can be initiated in cases and contacts as well as targeting
environmental measures and community education
A daily report of the number of cases and contacts as well as their treatment status and vital
status should be produced. A weekly report should summarize the outbreak situation and
summarize control measures taken and those planned to interrupt the outbreak.
International: Mandatory reporting of all suspected and confirmed cases within 24 hours to WHO.
WHO Recommended Surveillance Standards
October 97
87
RECOMMEND ED MINIMUM DATA ELEMENTS
Case-based data at peripheral level for investigation and reporting:
Case classification (suspected/probable/confirmed), unique identifier, name, geographical
information, age, sex, clinical syndrome, history of contact with rodents, presence of flea bites,
household or face to face contacts for previous seven days, names and geographical
information of contacts
Case-based data at central and regional level:
Case classification(suspected/probable/confirmed)
Unique identifier, age, sex, geographical area, number of contacts identified, number of contacts
treated
RECOMMENDED DATA ANALYSES, PRESENTATION, REPORTS
Cases by week/month, geographical area, age, sex
PRINCIPAL USES OF DATA FOR DECISION MAKING
• To detect trend in sporadic and endemic disease patterns
• To identify high risk areas
• To give early warning of outbreak
• To detect clusters of cases and outbreaks
• To confirm the impact of control measures and the end of an outbreak
SPECIAL ASPECTS:
- --------------- ---------------epizootic surveillance:
• Periodic surveys of rodent populations and plague activity in these populations alerts public
health authorities to increased human plague risks, thus allowing prevention and control
measures to be implemented before human cases occur.
• Serological surveillance of wild carnivore and outdoor-ranging dog and cat populations is
recommended in areas surrounding the' endemic ones.
• Ports close to endemic areas should be placed under surveillance and demanding periodic
sanitation to prevent rodent population to increase.
Countries with endemic areas must have a risk assessment policy for every new development work
that could change local ecology (e.g. roads, dams, agriculture)
CONTACT
Regional offices
See Regional Communicable Disease contacts on pages 15-20
Headquarters
WHO Division of Emerging and other Communicable Diseases Surveillance and Control (EMC)
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: tikhomirove@who.ch /outbreakemc@who.ch
Tel: (41 22) 791 2656 / 2850 / 2111
Fax: (41 22) 791 4878 / 0746 attn EMC
WHO Recommended Surveillance Standards
October 97
88
Poliomyelitis
A36
Poliomyelitis
RATIONALE FOR SURVEILLANCE
Targeted for eradication (9GPW 6.1). Highly sensitive surveillance for acute flaccid paralysis
(AFP), including immediate case investigation; specimen collection is critical to detect wild
poliovirus circulating in every infected geographical area with the ultimate objective of polio
eradication.
RECOMMENDED CASE DEFINITION
Clinical case definition
Any child under fifteen years of age with acute, flaccid paralysis1 or any person with paralytic
illness at any age when polio is suspected
Case classification
Suspected case: A case that meets the clinical case definition
Confirmed case: See diagram in section "special aspects requiring explanation"
11ncluding Guillain Barre syndrome
_________________________________________
RECOMMENDED TYPES OF SURVEILLANCE
Aggregated data of AFP cases should be included in routine monthly surveillance reports.
Zero reporting should be required at all levels.
All outbreaks should be investigated immediately.
AFP cases (possible polio cases) should be reported immediately, investigated within 48 hours
(case-based data), and stool specimens collected within 14 days of paralysis onset.
Active surveillance should be implemented in selected hospitals.
RECOMMENDED MINIMUM DATA ELEMENTS
Aggregate data:
• Number of third doses of oral polio vaccine (OPV3) administered to infants
• Number of AFP cases
Case based data (to be linked to specimen-based data for analysis),
• Unique identifier, geographical area name, province name, date of birth, date of paralysis, date
of notification, date of case investigation
• Total polio vaccine doses received, fever at onset of paralysis(yes/no/unknown), progression
of paralysis within 4 days(yes/no/unknown), asymmetric paralysis(yes/no/unknown), date of
60-day follow-up exam, findings at 60-day follow-up(residual weakness/no residual
weakness/lost to follow-up/death before follow-up)
• Final classification(confirmed/compatible/discarded/vaccine-associated)
Specimen-based data (to be linked to case-based data for analysis)
• Unique identifier, specimen number(first specimen/second specimen/unknown)
• Date of paralysis onset, date of last OPV, date of stool specimen collection, date stool
specimen sent to lab, date specimen received in lab
•
Condition of stool(good/poor/unknown)
• Date final culture results sent from lab, date intra-typic differentiation results sent from lab to
EPI.
Results Polio isolated? Polio type 2 isolated? Polio type 3 isolated?
Specify result: wild/Sabin/ pending intra-typic differentiation/mixture of wild & Sabin
P(1/2/3)/no P(1/2/3)isolated/specimen not processed
Non-polio enterovirus (NPEV) isolated? (yes/no NPEV isolated/specimen not processed)
WHO Recommended Surveillance Standards
October 97
89
RECOMMENDED DATA ANALYSES, PRESENTATION, REPORTS
Aggregate data:
• Cases by month, year, and geographic area
• OPV3 coverage by year and geographic area
• Completeness/timeliness of monthly reporting
Case-based data: same as aggregate data plus the following:
• Confirmed cases by age group, immunization status, geographic area, month and year
• Confirmed cases from which wild poliovirus was isolated
• Cases with wild poliovirus by geographic area
• Compatible cases by geographic area
• All suspect cases by final classification
• Non-polio enterovirus isolation rate
Performance indicators of surveillance quality
• % of all expected monthly reports that were received
• Annualised non-polio AFP rate per 100 000 children <=15 years
• % of AFP cases investigated within 48 hours
• % of AFP cases with 2 adequate stool specimens collected > 24 hours
apart and < 14 days of onset
• % of specimens arriving at the laboratory in “good” condition
• % of specimens arriving at a WHO-accredited laboratory within 3 days
• % of laboratory results sent within 28 days of specimen receipt
target
> 90%
> 1/100 000
> 80%
> 80%
> 80%
> 80%
> 80%
PRINCIPAL USES OF DATA FOR DECISION-MAKING
• Track wild poliovirus circulation
• Classify cases as confirmed, polio compatible or discarded (see special aspects)
• Monitor routine coverage in all geographical areas and focus efforts in low performing
geographical areas
• Identify high risk areas for planning mopping up immunization
• Monitor seasonality to determine low season of poliovirus transmission for NIDs planning
• Monitor performance of surveillance using standard indicators and focus efforts in low
performing areas
>
• Provide evidence for polio-free certification
WHO Recommended Surveillance Standards
October 97
90
SPECIAL ASPECTS REQUIRING EXPLANATION:
The following two scheme should be used to classify AFP cases. A country should use the first
scheme until their surveillance performance meets the following three criteria: 1) a non-polio AFP
rate of at least 1/100 000 children under 15 years of age; 2) two adequate specimens1 collected
from at least 60% of detected AFP cases; 3) all specimens processed in a WHO-accredited
laboratory.
confirm
Wild poliovirus
AFP
inadequate
specimens
No wild
poliovirus
residual
paralysis,
died or losf"
to follow-up
confirm
no residual
paralysis
discard
two adequate
Specimens'
discard
■>
Wild poliovirus
AFP
X
inadequate
specimens
No wild
poliovirus
residual
paralysis.
died or lost—► exPert
to follow-up
1review
------
confirm
compatible
discard
no residual
paralysis
■>
two adequate
Specimens’
discard
discard
1 "Adequate specimens” means two specimens collected 24-48 hours apart and within 14 days of
onset of paralysis. The specimen arriving at the laboratory must be of adequate volume
(approximately 8-10 grams) and in “good condition". “Good condition" = no leakage, no
desiccation, appropriate documentation (i.e. laboratory request form) and evidence that the
reverse cold chain was maintained (based on presence of ice or temperature indicator).
2 "compatible” cases indicate surveillance failures and should be monitored for clustering in space
and time
CONTACT
Regional offices
See Regional Communicable Disease contacts on the pages 15-20
Headquarters
Expanded Programme on Immunization (EPI)
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: hullh@who.ch
Tel: (41 22) 791 4409/2111
Fax: (41 22). 791 4193 attn EPI______________ __
WHO Recommended Surveillance Standards
October 97
91
Rabies
A82
Rabies
RATIONALE FOR SURVEILLANCE
Rabies is present on all continents and is endemic in most African and Asian countries. It is a fatal
zoonotic viral disease which is transmitted to humans through contacts (mainly bites and scratches)
with infected animals both domestic and wild. Over 40 000 human deaths are estimated to occur
each year world-wide most of them in the developing world, mainly in Asian countries. An estimated
10 million people receive post exposure treatments each year after being exposed to rabies
suspected animals.
WHO promotes human rabies prevention by well-targeted post exposure treatment and increased
availability of modern rabies vaccine as well as disease elimination by mass vaccination of dogs and
other animal reservoir species. Surveillance of both human and animal rabies is essential to rapidly
detect high risk areas and outbreaks and to monitor the use of vaccine.
RECOMMENDED CASE DEFINITION
Clinical description
An acute neurological syndrome (encephalitis) dominated by forms of hyperactivity (furious rabies)
or paralytic syndromes (dumb rabies) that progresses towards coma and death usually by
respiratory failure within 7 to 10 days after the first symptom if no intensive care are instituted. Bite
or scratch from a suspected animal can usually be traced back in the patient medical history. The
incubation period may vary from days to years but usually falls between 30 to 90 days.
Laboratory criteria for diagnosis
one or more of the following
• Detection by fluorescent antibody (FA) on brain tissue (collected post mortem)
• Detection by FA on skin or comeal smear (collected ante mortem)
• FA positive after inoculation of brain tissue, saliva or CSF in cell culture, mice or suckling mice
• Detectable rabies-neutralising antibody titre in CSF of an unvaccinated person
• Identification of viral antigens by PCR on fixed tissue collected post mortem or in a clinical
specimen (brain tissue or skin, cornea or saliva)
Case classification
HUMAN RABIES:
A case that is compatible with the clinical description
Suspected:
A suspected case with an history of contact with a suspected rabid animal
Probable:
A suspected case that is laboratory-confirmed
Confirmed:
HUMAN EXPOSURE TO RABIES:
Possibly exposed: A person who had a close contact (usually a bite or scratch) with a rabies
susceptible animal in/or originating from a rabies infected area
A person who had a close contact (usually a bite or scratch) with a laboratoryExposed:
confirmed rabid animal.
RECOMMENDED TYPES OF SURVEILLANCE
SURVEILLANCE IN HUMAN POPULATION:
Surveillance of human exposure to rabies: At peripheral level especially in rabies infected area,
reports of patients with a history of animal contact (usually a bite/scratch) should be
immediately investigated and when required they should be treated as an emergency. Case
based and aggregated data must be sent regularly from peripheral to intermediate and central
level.
WHO Recommended Surveillance Standards
October 97
93
Surveillance of cases of human rabies: Immediate reporting of suspected and confirmed cases
from peripheral level (by diagnosing physician and laboratory) to intermediate and central level.
Rapid exchange of information with services in charge of animal rabies surveillance and control
is required.
Epidemiological investigation of outbreaks: Investigation of every rabies foci, identifying sources
of infection as will as humans and animals exposed or possibly exposed
SURVEILLANCE IN ANIMAL POPULATION (EPIZOOTIC CONTROL): Immediate submission of
brain specimen of suspected animal for laboratory diagnosis when human exposure occurs.
Suspected domestic animals at the origin of human exposure which cannot be killed, should be
kept in observation for 10 days. Surveillance of animal rabies and similar conditions in wild and
domestic species most likely to be reservoirs of disease, must be undertaken in countries
where the disease is endemic or has the potential to be reintroduced. The surveillance is
laboratory based. Rapid exchange of information between services in charge of human and
animal rabies surveillance and control is required.
RECOMMENDED MINIMUM DATA ELEMENTS
"
- -------------------------------HUMAN RABIES EXPOSURE
case-based data: Unique identifier, name, age, geographical information, date(s) of bite/scratch,
geographical information (location) of biting episode(s), category of exposure, local wound
treatment, vaccination history, previous serum treatment, treatment, outcome; details of biting
animal, vaccination history, outcome
aggregate data: Exposures by geographical information on biting episode, biting animal, outcome in
the animal and human
HUMAN RABIES DEATHS SURVEILLANCE:
Unique identifier, name, age, geographical information, date of onset of symptoms, date(s) of
bite/scratch, geographical information (location) of biting episode(s), site of bite on the body,
nature of bite, local wound treatment, vaccination history, previous serum treatment, hospital,
treatment details, outcome, details of biting animal, samples taken, sample results
RECOMMENDED DATA ANALYSES, PRESENTATION, REPORTS
Number of human rabies deaths and rabies cases in animals (by species) by dates of presentation.
Human exposures by location and dates of biting/scratch episode^ by animal species at the origin of
exposure and by outcome in human and in animal populations.
Cases by geographical area (e.g. district) and dates of biting/scratch episode, type of animal,
occupation and outcome.
PRINCIPAL USES OF DATA FOR DECISION MAKING
• Detect outbreaks in endemic areas and new cases in rabies-free area
• Determine high-risk areas for intervention
• Rationalise the use of vaccine and immunoglobulin
• Evaluate effectiveness of intervention at the level of the animal reservoir and exposed human
population
SPECIAL ASPECTS
Intersectoral co-operation between medical and veterinary services as will as community
involvement and participation are needed for targeted response and control in animal reservoir.
CONTACT
Regional offices
See Regional Communicable Disease contacts on pages 15-20
Headquarters:
Division of Emerging and other Communicable Diseases Surveillance and Control (EMC)
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: meslinf@who.ch / outbreakemc@who.ch
Tel: (41 22) 791 2575 /2111 Fax: (41 22) 791 4893 attn EMC
WHO Recommended Surveillance Standards
October 97
94
Salmonellosis
A02.0
Salmonellosis
RATIONALE FOR SURVEILLANCE
Salmonellosis has emerged as one the greatest causes of foodborne disease. The detection and
control of outbreaks associated with this organism is complicated by the fact that there are over
2 200 serotypes of Salmonella sp„ several of which have multiple phage types. Laboratory-based
surveillance of salmonellosis with definitive typing and antibiograms allows for the rapid identification
of clusters of cases. Investigations can then concentrate on case with the “epidemic" strain leading
to better identification of risk factors and implicated food items. Utilisation of molecular methods can
lead to even more accurate identification of “epidemic" strains.
RECOMMENDED CASE DEFINITION
Laboratory criteria for confirmation
Isolation of Salmonella sp. from the stool or blood of a patient
Case classification
A case in whom laboratory investigation confirms the presence of Salmonella
Confirmed:
species
An outbreak: An incident in which two or more persons experience a similar illness after what is
thought to have been a common exposure (ingestion of the same food or after
ingestion of water of the same source)
An outbreak of salmonellosis: An outbreak where two or more cases are epidemiologically
linked (e.g. place, time, food product)
RECOMMENDED TYPES OF SURVEILLANCE
National: The surveillance of salmonellosis is a laboratory based exercise. However the samples
examined by laboratories must be generated from cases presenting at health centres, private
practitioners and hospitals. To this end practitioners must be aware of the importance of requesting
examination of stool specimens for public health purposes, especially in cases where food or water
borne transmission is suspected.
Surveillance of salmonellosis should be based on a network of laboratories that routinely report data
on isolation of Salmonella sp. to more central levels. In addition, isolates of Salmonella sp. may be
sent to a reference laboratory for more definitive typing. At more central levels, definitive typing data
can be analysed on a broader geographical basis allowing for the detection of outbreaks that may
not otherwise be detected.
All suspected outbreaks of salmonellosis should be reported to the central level and investigated.
A minimum data set should be collected on each outbreak at intermediate and central level. This
should be done after the outbreak investigation and should include key variables describing the
nature and extent of the outbreak.
Note: The laboratory network for surveillance of salmonellosis should be as wide and complete as
possible. The concentration of facilities for definitive typing in reference laboratories is useful
in order to maintain quality. However, care must be taken in relying on the samples processed
in such laboratories as they may not always be representative in terms of clinical spectrum or
geography.
WHO Recommended Surveillance Standards
October 97
95
International: All major foodborne disease outbreaks, particularly those implicating a commercial
product, should be reported to the Food Safety Unit, global databank on foodborne disease
outbreaks (under development), and regional programmes for surveillance of foodborne diseases.
ENTER-NET (previously SALM-NET) is an international network of where information on
laboratory isolations of salmonellosis and Escherichia coli 0157 is shared between countries in the
network on much the same basis as within countries. This allows for the detection of outbreaks of
international significance and the early warning of countries about contaminated products etc.
RECOMMENDED MINIMUM DATA ELEMENTS
Case-based data from laboratory
Unique identifier, age, sex, geographical information
Date of onset, date of specimen
Specimen type, organism(s) identified
Aggregated data from laboratory
Number of cases by Salmonella sp., geographical area and age group
Outbreaks aggregated data:
Specific salmonella species and phage type identified
Number of people at risk/ill/hospitalised/dead
Geographical information, outbreak setting (e.g. restaurant, hospital, school)
Date of first and last case
Food or constituent implicated and evidence for implication (e.g. epi study, isolation in food)
Factors contributing to the outbreak (e.g. inadequate storage, inadequate heating, cross
contamination, infected food handler, environmental factors)
RECOMMENDED DATA ANALYSES, PRESENTATION, REPORTS
Surveillance data
Frequent review of laboratory data looking for clusters of case in time, place or person. All
suspected clusters should be investigated to establish whether an outbreak has occurred
Incidence of laboratory identifications by week, geographical area, organism, age group and
sex (map incidence by geographical area if- possible)
Outbreak investigation data
Incidence of outbreaks by species, phage type, month, geographical area, setting of outbreak,
attack-rate, duration of outbreak, foods implicated and factors contributing to the outbreak
PRINCIPAL USES OF DATA FOR DECISION MAKING
Determine the magnitude of the public health problem
Timely detection of clusters/outbreaks
Track trends in salmonellosis over time
Identify high-risk food, high-risk food practices and high-risk populations for specific pathogens.
Identify emergence of new species and phage types
Guide the formation of food policy and monitor the impact of control measures
Risk assessment and standard setting
SPECIAL ASPECTS
"
"
Human surveillance should be linked with food safety and control authorities.
CONTACT
------------ —.... .................
Regional offices
See Regional Communicable disease contacts on pages 15-20
Headquarters
Programme of Food Safety and Food Aid (FSF), 20 Avenue Appia, CH-1211 Geneva 27 Switzerland
E-mail: motarjemiy@who.ch
Tel: (41 22) 791 3558/3535/2111
Fax: (41 22) 791 4807 attn FSF
WHO Division of Emerging and other Communicable Diseases Surveillance and Control (EMC)
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: outbreakemc@who.ch Tel: (41 22) 791 2529/2660/2111
Fax: (41 22) 791 4893
WHO Recommended Surveillance Standards
October 97
96
Schistosomiasis
B65
Schistosomiasis
RATIONALE FOR SURVEILLANCE:
Schistosomiasis is the second most prevalent tropical disease (following malaria) and a leading
cause of severe morbidity in large parts of Africa, Asia and South America. 600 million are at risk;
200 million are infected, of whom 20 million are severely ill.
The main goal for WHO is to control the disease, to reduce and even eliminate (in some countries)
the risk of schistosomiasis through strong surveillance and control programmes.
There are different clinical diseases: Urinary Schistosomiasis (due to S. haematobium) and intestinal
schistosomiasis (due to S. mansoni, S. japonicum, S. intercalatum, S. mekongi).
RECOMMENDED CASE DEFINITION:
URINARY SCHISTOSOMIASIS:
Case definition and classification
endemic area
Suspected:
Probable:
Confirmed:
Suspected.
Probable:
Confirmed:
Not applicable
Not applicable
A person with visible haematuria
or with positive reagent strip for haematuria
or with eggs of 8. haematobium in urine (microscope)
non-endemic area
A person with visible haematuria
or with positive reagent strip for haematuria
Not applicable
A person with eggs of S. haematobium in urine (microscope)
INTESTINAL SCHISTOSOMIASIS
Case definition and classification
Suspected.
Probable:
Confirmed:
Suspected:
Probable:
Confirmed:
endemic area
A person with hepatosplenomegaly
Not applicable
A person with eggs of S. mansoni or S. japonicum in stools (microscope)
non-endemic area
Not applicable
Not applicable
A person with eggs of S. mansoni or S. japonicum in stools (microscope).
RECOMMENDED TYPES OF SURVEILLANCE:
Surveillance of schistosomiasis should be incorporated in the primary health care system.
For low-prevalence zones and where eradication is targeted:
Routine monthly reporting of aggregated suspected or confirmed cases from peripheral level to
intermediate and central level.
International: Yearly reporting from central level to WHO
For endemic zones:
If no integration of surveillance is possible in the primary health care system: Ad hoc surveys
to evaluate the prevalence of infection in the community. Children of school age have been
identified as a appropriate group for investigation (a good indicator of prevalence in the general
population).
Yearly reporting of aggregated data from peripheral level to intermediate and central level.
WHO Recommended Surveillance Standards
October 97
97
Note
"
---------------------------• Data from general health statistics often underestimate the prevalence but may nevertheless
indicate a prevalence comparatively high in a particular area.
• The surveillance has to take into account the distribution of the disease in geographical foci.
Adjacent areas may have very different prevalence.
RECOMMENDED MINIMUM DATA ELEMENTS:
"
FOR LOW-PREVALENCE ZONES AND WHERE ERADICATION IS TARGETED’
individual patient record for investigation:
Identification number, age, place of infection, date of diagnosis, village
Number of eggs per gram of stools/per ml of urine
aggregated data:
Number of cases by age group and village and month
Number of cases with >50 eggs/10 ml of urine and /or visual haematuria for S. haematobium
Number of cases with >800 eggs/g of stools for S. mansoni or japonicum
FOR ENDEMIC ZONES:
aggregated data:
Number of cases by agegroup and village
Number of cases with >50 eggs/10 ml of urine and/or visual haematuria for S. haematobium
Number of cases with >800 eggs/g of stools for S. mansoni or japonicum
"RECOMMENDED DATA ANALYSES, PRESENTATION, REPORTS: ”———
• Incidence (if passive finding) monthly and yearly by agegroup and village
• Point prevalence (if active finding)
• Mapping
PRINCIPAL USES OF DATA FOR DECISION MAKING:
• Assess the magnitude of the problem '
• Plan drug distribution: select cost effective strategy for chemotherapy (Universal-TargetedSelective)
• Evaluate the need for snail control
• Evaluate the need for improved water supply and sanitation >
• Evaluate the need for health education activities
• Evaluate impact of intervention
SPECIAL ASPECTS
- ------------------------------------------------- -------------------------------------• Diagnosis: The quantitative diagnostic methods(Kato-Katz technique for intestinal forms, urine
filtration for S. haematobium) are very important in surveillance; They indicate the public health
relevance of the infection.
• Collection of data immediately relevant to management decision (e.g., treatment frequency and
resource allocation) should be encouraged.
• Intersectoral efforts, emphasising school education, safe water supply and sanitation,
environmental management and community participation, are important.
• Rectal biopsy usually not used for surveillance purpose.
C O N TA C T
Regional offices
See Regional Communicable Disease contacts on pages 15-20
Headquarters
WHO Schistosomiasis and Intestinal Parasites Unit (SIP)
20 Avenue Appia CH-1211 Geneva, Switzerland
E-mail: saviolil@who.ch
Tel: (41 22) 791 2664
Fax: (41 22) 791 4869
WHO Recommended Surveillance Standards
October 97
98
Note
•
Data from general health statistics often underestimate the prevalence but may nevertheless
indicate a prevalence comparatively high in a particular area.
• The surveillance has to take into account the distribution of the disease in geographical foci.
Adjacent areas may have very different prevalence.
RECOMMENDED MINIMUM DATA ELEMENTS:
FOR LOW-PREVALENCE ZONES AND WHERE ERADICATION IS TARGETED:
individual patient record for investigation:
Identification number, age, place of infection, date of diagnosis, village
Number of eggs per gram of stools/per ml of urine
aggregated data:
Number of cases by age group and village and month
Number of cases with >50 eggs/10 ml of urine and /or visual haematuria for S. haematobium
Number of cases with >800 eggs/g of stools for S. mansoni or japonicum
•
FOR ENDEMIC ZONES:
aggregated data:
Number of cases by agegroup and village
Number of cases with >50 eggs/10 ml of urine and/or visual haematuria for S. haematobium
Number of cases with >800 eggs/g of stools for S. mansoni or japonicum
RECOMMENDED DATA ANALYSES, PRESENTATION, REPORTS:
• Incidence (if passive finding) monthly and yearly by agegroup and village
• Point prevalence (if active finding)
• Mapping
PRINCIPAL USES OF DATA FOR DECISION MAKING:
• Assess the magnitude of the problem
• Plan drug distribution: select cost effective strategy for chemotherapy (Universal-TargetedSelective)
• Evaluate the need for snail control
•
Evaluate the need for improved water supply and sanitation
• Evaluate the need for health education activities
•
Evaluate impact of intervention
SPECIAL ASPECTS
• Diagnosis: The quantitative diagnostic methods(Kato-Katz technique for intestinal forms, urine
filtration for S. haematobium) are very important in surveillance; They indicate the public health
relevance of the infection.
• Collection of data immediately relevant to management decision (e.g., treatment frequency and
resource allocation) should be encouraged.
• Intersectoral efforts, emphasising school education, safe water supply and sanitation,
environmental management and community participation, are important.
• Rectal biopsy usually not used for surveillance purpose.
CONTACT
Regional offices
See Regional Communicable Disease contacts on pages 15-20
Headquarters
WHO Schistosomiasis and Intestinal Parasites Unit (SIP)
20 Avenue Appia CH-1211 Geneva, Switzerland
E-mail: saviolil@who.ch
Tel: (41 22) 791 2664
Fax: (41 22) 791 4869
WHO Recommended Surveillance Standards
October 97
98
Scrub typhus
A 75.3
Scrub typhus
(Tsutsugamushi disease)
RATIONALE FOR SURVEILLANCE
- ------------------- -------------------------------Scrub Typhus (Tsutsugamushi disease) is an acute infectious disease that is emerging and reemerging in Southeast Asia and the south-western Pacific region. This disease can have a case
fatality up to 30 %, if untreated. Scrub Typhus is probably one of the most underdiagnosed and
underreported febrile illness requiring hospitalisation in the region. Epidemics occur when
susceptibles are brought into endemic areas(e.g. military operations). In some countries (e.g.
Japan) it is a notified disease.
Surveillance is essential in order to understand better the epidemiology of the disease and to detect
outbreaks. In addition training in diagnostic techniques will be necessary.
RECOMMENDED CASE DEFINITION
”
—------------------Clinical description
A disease with primary a “punched out” skin ulcer (eschar)*, followed by acute onset fever after
several days, along with headache, profuse sweating, conjunctival injection and lymphadenopathy.
Dull maculo-papular rash** in the trunk extends to the extremities which appears in few days. Cough
is also common. Sensitivity to tetracycline’s derivatives is a basis also for notification.
Laboratory criteria for diagnosis
Isolation of Rickettsia tsutsugamushi by inoculation of patient blood in white mice (preferably treated
with cyclophosphamide at 0.2 mg/g ip or im on days 1,2 and 4 after inoculation)
Serology: Detection of specific IgM at 1:32 dilution or higher by Immunoperoxidase (IP) or at 1:10 or
higher by Indirect Immunofluorescence (IF)
.
Case classification
Suspected:
A case that is compatible with the clinical description
Confirmed:
A suspected case with laboratory confirmation
Note:
Serological tests are complicated by the antigenic differences of various strains of the
causal rickettsia.
'Eschar is absent in re-infection at heavily infested areas.
** The rash on the sunburned skin is often overlooked in the tropics.
RECOMMENDED TYPES OF SURVEILLANCE
Immediate case-based reporting of all suspected cases from the peripheral level to the intermediate
and central level. All suspected cases and outbreaks must be confirmed. A parallel laboratory,
surveillance system reports all confirmed cases to central level.
WHO Recommended Surveillance Standards
October 97
99
RECOMMENDED MINIMUM DATA ELEMENTS
Case-based data to report
Case classification (suspected/confirmed)
Unique identifier, age, sex, geographical information
Date of report
Hospitalisation (Y/N)
Outcome
Aggregated data to report
Number of cases by case classification, age, sex, geographical information, date of report
Number of hospitalisations
Number of deaths
RECOMMENDED DATA ANALYSES, PRESENTATION, REPORTS:
Graphs: Number of cases by date of report
Tables: Number of cases by age, geographical area
Maps: Number of cases by geographical area
Case fatality
PRINCIPAL USES OF DATA FOR DECISION MAKING
• Detect outbreaks
• Monitor trends in endemic disease
• Monitor changes in epidemiology and pattern of disease
SPECIAL ASPECTS
The distribution of R. tsutsugamushi extends north to Japan, Russia, and the Primorske Karai
region in the Russian Far East, South to northern Australia and the western Pacific islands, and
west to Afghanistan, Pakistan, and in areas neighbouring the former USSR.
Human R. tsutsugamushi occurs widely in these regions, but not everywhere.
Scrub Typhus is probably one of the most underdiagnosed and underreported febrile illness
requiring hospitalisation in the region. The absence of definitive signs and symptoms combined with
a general dependence upon serological tests, made the differentiation of scrub typhus from other
common febrile diseases such as murine typhus, typhoid fever and leptospirosis quite difficult
CONTACT
Regional offices
WHO Regional Office for South-East Asia (SEARO)
Acting Director, Integrated Control of Diseases (ICD)
fax: 00 91 11 331 8412
Dr A.G. Andjaparidze, Regional Adviser on Communicable Diseases (CDA),
Direct telephone: 00 91 11 331 7804 to 7823
Fax 00 91 11 331 8412
E-mail: ANDJA@WHO.ERNET.IN
WHO Regional Office for the Western Pacific (WPRO)
Dr Shigeru Omi, Director, Disease Prevention and Control (DPC)
Direct telephone 00 632 522-9961, fax 00632 521-1036
E-mail: OMIS@WHO.ORG.PH
Dr Kouichi Morita, Regional Adviser in Communicable Diseases, CDS(M)
Direct telephone 00 632 522 9964, fax 00 632 521 1036
E-mail: MORITAK@WHO.ORG.PH
WHO Recommended Surveillance Standards
October 97
100
Syphilis
A50-52
Syphilis
RATIONALE FOR SURVEILLANCE
Having dropped after the introduction of Penicillin treatment in 1946, syphilis re-emerged in the end of the
sixties remaining at high incidence levels in developing countries. Also developed countries are now
experiencing outbreaks and economies in transition are experiencing wide recrudescence.
Syphilis prevalence in pregnant women provides information about latent and symptomatic syphilis in this
group, minimising the problems associated with reporting of STD syndromes, subject to influence of health
care seeking behaviour and can be considered an approximation of syphilis prevalence in the general
population.
This information will be utilised for assessment, policy making, planning and evaluation of STD
management activities.
RECOMMENDED CASE DEFINITION
---------------------------------A person with a confirmed positive serology for syphilis (Rapid Plasma Reagin (RPR) or VDRL
confirmed by TPHA or FTA- ABs)
RECOMMENDED TYPES OF SURVEILLANCE
Laboratory-based surveillance through screening of pregnant women
Routine reporting from antenatal (AN) clinics and sentinel sites of AN clinics
Active case finding from prevalence surveys in pregnancy
Only confirmed cases should be reported to intermediate and central level by
- routine case-based or aggregate reporting
- routine periodic surveillance reports
■
RECOMMENDED MINIMUM DATA ELEMENTS
Aggregate data
Number of cases of positive serology for syphilis by age group/month/geographical area
Number of cases of congenital syphilis by age group, gravida, years, geographical area
Performance indicators
False positive rate sentinel site by number tested by TPHA /FT-AB
RECOMMENDED DATA ANALYSES, PRESENTATION, REPORTS
Cases/incidence by geographical area, age, parity - table format see example SSS manual WHO.
Comparisons with age group and geographical area in previous years - line graph.
Rate of congenital syphilis by geographical area by year - line graph.
Annual surveillance summaries should be produced nationally and regionally and fed back.
PRINCIPAL USES OF DATA FOR DECISION MAKING
• Document syphilis prevalence by screening pregnant women as a surrogate for general
population
• Monitor trends in disease incidence
• Advocate Syphilis control, and interventions
• To identify high risk areas for further targeting intervention
WHO Recommended Surveillance Standards
October 97
101
SPECIAL ASPECTS:
• The prevalence rate varies between 3-19 % in pregnant women in developing countries
(associated with spontaneous abortion and stillbirth and congenital syphilis (one third infants).
Because the primary lesion is often painless and secondary syphilis is usually not diagnosed,
women are mainly identified by serological screening. Therefore it is recommended that syphilis
surveillance is best performed in pregnant women.
• In order to screen all pregnant women as per national policy guidelines women should attend
early for antenatal care, clinic staff should take blood and send it to lab, lab staff should report
results to clinic, women should attend for next visit and receive results and clinic staff are
supposed to treat and provide health education.
• Syphilis in cases of genital ulcer should be reported separately in countries with access to
laboratory facilities.
CONTACT
Regional offices
See Regional Communicable Disease contacts on pages 15-20
Headquarters
Office of HIV/AIDS and Sexually Transmitted Diseases (ASD)
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: gerbasea@who.ch
Tel: (41 22). 791 4658 /2111
Fax: (41 22) 791 4834 attn ASD
ao
•;;
OS 182
-'7' '•b.
i/L-f
AMD
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WHO Recommended Surveillance Standards
October 97
102
African trypanosomiasis
B56-0, B56-1
African trypanosomiasis
(Sleeping sickness)
RATIONALE FOR SURVEILLANCE-----------------------------------------------------------------------------------The leading principle for sleeping sickness control is the reduction of human reservoir throuah
treatment of infected individuals and the reduction of man-fly contact through ada^d vecS control
An intercountry approach for surveillance/control activities is essential and supported by WHO The
RECOMMENDED CASE DEFINITION
Clinical description
mav bZInunriTtb 3
-- ------------------ --------------------------------------
’ WhiCh ori9inates as a PaPule and then evolves into a nodule
T^a^Za'bruceTgX
rapid and acute evolution. Both diseases are always fatal without treatment.
Laboratory criteria for diagnosis
Presumptive: serological: Card agglutination trypanosomiasis test (CATT) for T.b. gambiense only
or immunofluorescent assay (IFA) for T.b. rhodesiense mainly and
.
possibly for T.b. gambiense
onfirmative: parasitological: detection(microscopy) of trypanosomes in blood lymph nodes
aspirates or CSF
>
Case classification
Suspected:
A case that is compatible with the clinical description or is exposed to the risk**
Probable:
A case with a positive serology with or without clinical symptoms
Confirmed'.
A case with positive parasitology with or without clinical symptoms***
I
painful chancre is very rare in T. b. gambiense
I a'renn?clini^|S«inn'n ‘P®
Sta9e °r eVen the early part of the late sta9e of the disease ^ere
92 °r ^nnPtoms which can be associated with the disease. Suspicion is then
•"ConS^a^Sf °f b°n|^Ctln9 th6 d'S6aSe and d'Sease historical background in the area.
6 ea hy carners are a maj°r Public heaitfl risk, they are a reservoir of
parasites, they disseminate the disease. They must be treated as soon as possible.
RECOMMENDED TYPES OF SURVEILLANCE--------------------------------------------------------------------• The surveillance system will use a village-based definition using 4 classes:
• village of unknown epidemiological status
• suspected village
• endemic village
• disease-free village
In the context of control programmes, surveillance provides valuable village-based data with the
precise geographic location of each village using global positioning system (GPS) Data are
analysed, using geographical information systems (GIS).
In areas not covered by control activities, surveillance provides valuable case-based
information. Results of serological surveys based on micro-CATT will be indicators of endemicity
» \A/uAtlOn co ected at vllla9e level, are aggregated at intermediate/central level and reported
IO WHO
WHO Recommended Surveillance Standards
October 97
103
RECOMMENDED MINIMUM DATA ELEMENTS
—
village-based data: In addition to number of parasitologically confirmed cases (presence of
trypanosome demonstrated), and number of probable cases (suspected cases
with positive serology)
the system should include information on
• strategy used
• village geographic co-ordinates (latitude, longitude)
• name
• administrative levels
• village type
• population at last census/date of last census, estimated population
• school (levels)
• health infrastructures (type, activities)
• protected source of water
RECOMMENDED DATA ANALYSES, PRESENTATION, REPORTS:
Mapping: at intermediate and central level: map of villages and their endemic status
PRINCIPAL USES OF DATA FOR DECISION MAKING
• Knowledge of endemic and suspected areas to direct control activities
• Epidemiological monitoring of endemic foci
• Assessing impact of control programmes
SPECIAL ASPECTS
• Use of Global Positioning System (GPS) to define village geographic co-ordinates
• Sensitivity of parasitological techniques is low and depends on lab facilities and personnel skills
CONTACT INFORMATION
Regional offices
WHO Regional Office for Africa (AFRO)
Dr D. Barakamfitiye, Director, Prevention and Control of Diseases (DDC)
Direct telephone 1 407 953 92 29, fax 1 407 953 9413
)
Dr A. Ndikuyeze, A/Regional Adviser, Prevention and Control of Diseases (DDC)
Direct telephone: 1 407 953 92 45
Dr S. Van Nieuwenhove, Medical Officer, Prevention and Control of Diseases
Direct telephone: 1 407 953 92 36
AFRO@WHO.ORG
E-mail:
ADIKPETOE@WHO.ORG
BARAKAMFITIYED@HTSD.COM at INET
DALME1DAA@HTSD.COM at INET
KOUBAT1KAK@HTSD.COM at INET
NDIKUEZEA@ HTSD.COM at INET
SAMBAE@ HTSD.COM at INET
VANNIEUWENHOVES@MAILHST.COM
Headquarters
WHO Division of Control of Tropical Diseases (CTD)
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: cattandp@who.ch / ctd@who.ch
Tel: (41 22) 791 3880 / 4478/ 2111
Fax: (41 22) 791 4777/ 0746 attn CTD
E-mail: janninj@who.ch / ctd@who.ch
Tel: (41 22) 791 3779 / 4478/ 2111
Fax: (41 22) 791 4777/ 0746 attn CTD
WHO Recommended Surveillance Standards
October 97
104
American trypanosomiasis
B57
American trypanosomiasis
(Chagas disease)
RATIONALE FOR SURVEILLANCE
• Targeted by WHO for elimination by the year 2000 . It affects 17 countries with over 100 million
individuals at risk of infection and 16-18 million infected
• Chagas disease is still prevalent in the northern part of South America (the Andean Region) and
in Central America where it poses a threat to almost 25 million of people and there are 5 to 6
million persons infected
• Potentially fatal and non treatable, a third of those infected become incapacitated due to cardiac
damage
• Infection can also be acquired through blood transfusion.
• The infection can be effectively eliminated through interruption of vector transmission and
systematic screening of blood donors. Elimination has been very successful in some countries
of the Southern Cone of South America (Argentina, Brazil, Bolivia, Chile, Paraguay and
Uruguay.)
• Surveillance is necessary to monitor prevention and control measures
RECOMMENDED CASE DEFINITION
ACUTE STAGE
Clinical description
The main clinical signs are mainly fever, malaise, hepatosplenomegaly and lymphadenopathy in the
acute phase. Many patients present without clinical signs. An inflammatory response at the site of
infection (chagoma) may last up to 8 weeks
Laboratory criteria for diagnosis
>
• Positive parasitology (direct, xenodiagnosis, blood culture) and /or
• Positive serology for 7". cruzi antibodies (IgM)
(indirect haemagglutination test (IHA), indirect immunoflourescent antibody test (IFAT), direct
agglutination test (DA) and ELISA)
Case classification
Suspected:
Not applicable
Probable:
In endemic areas: a person having unexplained fever, hepatosplenomegaly and a
“chagoma “ (inflammation at site of infection)
Confirmed:
A clinically compatible case that is laboratory-confirmed
INDETERMINATE STAGE: Positive serology for T. cruzi antibodies
CONGENITAL: Hepatosplenomegaly with positive xenodiagnosis in a new-born in endemic areas
BLOOD DONOR: Positive serology for Chagas
RECOMMENDED TYPES OF SURVEILLANCE
In endemic areas, sentinel surveillance may be the only feasible method at present.
Where possible, routine surveillance of American trypanosomiasis should be integrated in primary
health services. At peripheral level individual patient records should be maintained. Routine monthly
reporting of aggregated data from peripheral level to intermediate level. Routine biannual reporting
of aggregated data to central level.
All blood donations should be screened locally.
Serological surveys (standardised and periodically) are used for surveillance and control.
WHO Recommended Surveillance Standards
October 97
105
RECOMMENDED MINIMUM DATA ELEMENTS
CLINICAL SURVEILLANCE
Individual patient records
Unique identifier, name, age, sex, geographical information, laboratory results
Aggregated data for reporting.
Number of cases identified from transfusion donors
Number of cases by age/ sex/ means of diagnosis
Number of cases with positive serology
(Number of houses or communities subject to vector control annually)
LABORATORY SURVEILLANCE
Isolate-based data for reporting (see WHO technical report series 811 page 78)
Scientific name of organism, clinical form, organ or tissue, geographical information(patient
location), date of isolation, name laboratory, laboratory number of isolate, identification methods
used, results
RECOMMENDED DATA ANALYSES, PRESENTATION, REPORTS
Graphs: Number of cases by geographical area, month, and means of diagnosis
Maps: Number of cases by geographical area
(Vector control activities / geographical area/ prevalence of disease)
PRINCIPAL USES OF DATA FOR DECISION MAKING
• Monitor disease prevalence and measure the impact of disease
• Monitor control and elimination programme
• Target resources for prevention
SPECIAL ASPECTS
• Control has until now depended on vertical programmes. Monitoring and surveillance have been
conducted during specific surveys. To integrate the control programme into PHC requires a
network of laboratory services with different facilities at different levels for diagnosis.
• Because of variation in specificity of the tests cut off points should be defined locally using
standard serum panel, provided by the reference laboratories of the intercontinental network for
standardised serology in Brazil and Argentina.
)
• A national laboratory network should be established in each of the countries in which Chagas
disease is endemic.
CONTACT
Regional Office
WHO Regional Office for the Americas (AMRO, PAHO)
Dr S. Corber, Director, Division of Communicable Disease Prevention and Control (HCP)
Direct telephone 001 202 974-3850, fax 001 202 974-3648 or 001 202 974-3643
E-mail: CORBERST@PAHO.ORG
Dr G. Schmunis, Co-ordinator, Programme of Communicable Diseases (HCP/HCT)
Direct telephone 001 202 861-3272 fax 001 202 861-8483
E-mail: SCHMUNIG@PAHO.ORG
Headquarters
WHO Division of Control of Tropical Diseases (CTD), Trypanosomiasis and Leishmaniasis Control
(TRY), 20 Avenue Appia CH-1211 Geneva, Switzerland
E-mail: moncayo@who.ch
Tel: (41 22) 791 3977 / 2662 72111
Fax: (41 22) 791 48 93 / 07 46 attn TDR
WHO Recommended Surveillance Standards
October 97
106
Tuberculosis
A15-A19
Tuberculosis
RAT10NALE FOR SURVEILLANCE
-- --------------------------------------------------------The overall objective of tuberculosis control is to reduce morbidity, mortality and transmission of the
disease until it no longer poses a threat to public health. To achieve this objective, in 1991 the World
Health Assembly endorsed the following targets for global TB control: to treat successfully 85% of the
detected new smear-positive cases and to detect 70% of them by the year 2000.
The magnitude of the global TB problem is enormous. About one third of the world’s population is
infected by Mycobacterium tuberculosis. World-wide some 3.3 million cases are notified every year
However, according to various estimates, between 7 and 8.8 million cases might occur 95% of which
in developing countries. Projections into the next century suggest that the impact of TB will further
increase if no adequate control is established immediately in all countries.
Surveiilance of TB serves the purpose of enabling an accurate picture to be obtained of the course of
the TB epidemic in a community over time and permitting timely intervention if the trend observed
deviates from what is expected.
RECOMMENDED CASE DEFINITIONS
- --------------------------Pulmonary tuberculosis, smear positive (PTB+):
• TB in a patient with at least two initial sputum smear examinations (direct smear microscopv)
positive for Acid Fast Bacilli (AFB), or
• TB in a patient with one sputum examination positive for AFB and radiographic abnormalities
consistent with active pulmonary TB as determined by the treating medical officer, or
• positivefor AFBVith 006 SPUtUm specimen Pos'tive for AFB and at least one sputum that is culture
Pulmonary TB, smear negative (PTB-):
| TB in a patient with symptoms suggestive of TB and having one of the following:
two sets (taken 2 weeks apart) of at least 2 sputum specimens negative for AFB; radiographic
abnormalities consistent with pulmonary TB and a lack of clinical response despite one week of a
broad-spectrum antibiotic; a decision by a physician to treat with a full curative course of anti-TB
chemotherapy; or
• severely ill; at least 2 sputum specimens negative for AFB; radiographic abnormalities consistent
with extensive pulmonary TB (interstitial or miliary); a decision by a physician to treat with a full
curative course of anti-TB chemotherapy; or
• a patient whose initial sputum smears were negative, who had sputum sent for culture initially, and
whose subsequent sputum culture result is positive
Extra-pulmonary TB:
• TB of organs other than lungs: TB of pleura, lymph nodes, abdomen, genito-urinary tract, skin
joints and bones, TB meningitis, etc.
• ^iag2os,s should be based on one culture positive specimen from an extra-pulmonary site, or
histological or strong clinical evidence consistent with active extra-pulmonary TB, followed by a
decision by a medical officer to treat with a full course of anti-TB therapy
• Any patient diagnosed with both pulmonary and extra-pulmonary TB should be classified as a case
of pulmonary TB
New case; A patient who has never had treatment for TB or took anti-TB drugs for less than four
weeks
Relapse case: A patient previously treated for TB and declared cured by a medical officer after one
full course of chemotherapy, but who reports back to the health service bacteriological positive
•
RECOMMENDED TYPES OF SURVEILLANCE:
”
Quarterly reports on case notifications and on cohort analysis of treatment outcomes (at peripheral
intermediate, and central level).
WHO Recommended Surveillance Standards
October 97
107
RECOMMENDED MINIMUM DATA ELEMENTS
Case notifications by category:
• Number of new pulmonary sputum smear positive cases
• Number of pulmonary relapse cases
•
Number of new pulmonary sputum smear negative cases
• Number of new extra-pulmonary cases
• Number of new pulmonary sputum smear positive cases by age and gender (suggested age
groups: 0-14, 15-24, 25-34, 35-44, 45-54, 55-64, 65+ years)
Treatment results for new sputum smear positive cases:
(usually calculated as % out of all new sputum smear positive cases registered during the same period
of time)
• Number of cases who converted to negative after initial phase of treatment
•
Number of cases cured (i.e., completed treatment and at least two negative sputum smear result
during the continuation phase of treatment of which one was at end of treatment)
• Number of cases who, after smear conversion at the end of initial phase of treatment, completed
treatment, but without smear results at end of treatment
• Number of cases who died (regardless of cause)
• Number of cases who failed treatment (i.e., became again or remained smear positive five months
or later after starting treatment)
• Number of cases who interrupted treatment/defaulted (i.e., patient who did not collect drugs for two
months or more after registration)
• Number of cases who were transferred out (i.e., patient transferred to another reporting unit and
whose results are not known)
RECOMMENDED DATA ANALYSIS, PRESENTATION, REPORTS
Analysis of geographical area (district) quarterly reports:
•
Treatment success rate: proportion of cases which were cured plus completed treatment out of
cases registered during the same period of time
• Quality of diagnostic services: proportion of new sputum smear positives out of all pulmonary
cases
Presentation and reports:
Graphs:
• Case notification rates over several years by geographical area, regions, and total country
• Case notification rates (new sputum smear positives) by age and sex
• Case detection rate: proportion of TB cases occurring in the country which were detected by the
national TB control programme out of those estimated to have occurred
Tables:
Describe quarterly reports by case finding and treatment outcomes
PRINCIPAL USES OF DATA FOR DECISION-MAKING
• At local level: it ensures that appropriate treatment services are offered, contact tracing is carried
out, local outbreaks are recognised, and local epidemiology is monitored.
• At national level: it allows monitoring of the epidemiology of the disease in the country and of the
performance of treatment programmes (an NTP’s ability to detect TB cases, to diagnose sputum
positive cases, to successfully treat TB cases), and planning for programme activities (e.g. securing
drug supply, lab supply, etc.).
• At international level: it permits to examine trends over time and make inter-country comparisons
with the aim of co-ordinating control efforts.
CONTACT
Regional offices
See Regional Communicable Disease contacts on pages 15-20
Headquarters
Global Tuberculosis Programme (GTB)
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: raviglionem@who.ch
Tel: (41 22) 791 2663
WHO Recommended Surveillance Standards
October 97
Fax:(41 22) 791 2853 attn GTB
108
Yellow fever
A95
Yellow fever
Case report universally required by International Health Regulations
RATIONALE FOR SURVEILLANCE
This mosquito-borne virus disease occurs in tropical regions of Africa and South America and is
maintained by sylvatic transmission of virus involving forest-dwelling mosquitoes and monkeys.
Transmission to humans may occur in forest transition zones and may subsequently enter an urban
cycle through Aedes aegypti. Many cities are now threatened with major epidemics as yellow fever
is undergoing a major resurgence especially in the African region. Strategies for yellow fever control
include control of A. aegypti in urban centres, infant immunization, vaccination campaigns, outbreak
prevention, epidemic detection and control. Surveillance data allows for monitoring disease
incidence, prediction and early detection of outbreaks and monitoring of control measures. Case
report is universally required by International Health Regulations
RECOMMENDED CASE DEFINITION
Clinical description
An illness characterized by acute onset of fever followed by jaundice within 2 weeks of onset of first
symptoms.
Laboratory criteria for diagnosis
• Isolation of yellow fever virus, or
• Presence of yellow fever specific IgM or a four-fold or greater rise in serum IgG levels in paired
sera (acute and convalescent) or
• Positive post-mortem liver histopathology or
• Detection of yellow fever antigen in tissues by immunohistochemistry or
• Detection of yellow fever virus genomic sequences in blood Or organs, by PCR
Case classification
Suspected:
A case that is compatible with the clinical description
Probable:
Not applicable
Confirmed:
A suspected case that is laboratory-confirmed (national reference lab) or
epidemiologically linked to a confirmed case or outbreak
RECOMMENDED TYPES OF SURVEILLANCE:
Immediate reporting of suspected cases from peripheral to intermediate and central level.
All suspected cases and outbreaks must be investigated immediately and laboratory-confirmed.
Case-based surveillance must be implemented in countries identified by WHO as high risk for yellow
fever. Specimens must be collected to confirm an epidemic as rapidly as possible. Priority is placed
on collecting specimens from new or neighbouring areas (other than the area where the epidemic is
already confirmed).
Routine weekly/monthly reporting of aggregated data on suspected and confirmed cases from
peripheral to intermediate and central level.
International: Mandatory reporting of all suspected and confirmed cases within 24 hours to WHO.
4
WHO Recommended Surveillance Standards
October 97
109
RECOMMENDED MINIMUM DATA ELEMENTS:
Aggregated data for reporting
Number of cases
Doses of YF vaccine administered to infants, by geographical area
Completeness / timeliness of monthly reports
Case-based data for reporting and investigation
Unique identifier, geographical area, date of birth, date of onset, date of investigation
Ever received a dose of yellow fever vaccine (yes/no/unknown)
Date acute blood specimen received in laboratory
Date convalescent blood specimen received in laboratory (if applicable)
Date histopathology specimen collected
Depending on which laboratory tests used:
IgM results (positive/ negative/ no specimen processed/ unknown)
Virus isolation results (positive/ negative/ no specimen processed/ unknown)
IgG (4-fold rise) results (positive/ negative/ no specimen processed/ unknown)
Liver histopathology (positive/ negative/ no specimen processed/ unknown)
Date IgM results first sent, date virus isolation results first sent
Date IgG results first sent, date h- ••'□pathology report first sent
Final classification (confirmed/ suspected/discarded)
Final outcome (alive/ dead/ unknown)
RECOMMENDED DATA ANALYSES, PRESENTATION, REPORTS:
Aggregate data
Incidence rate by month, year, and geographic area
Yellow fever vaccine coverage by year and geographic area
Completeness/timeliness of monthly reporting
Case-based data same as aggregate data plus the following:
Confirmed cases by age group, immunization status, geographic area, month and year
Case fatality rate
Final classification of all suspected cases
Performance indicators of surveillance quality
Completeness of monthly reporting
Percent of all suspect cases for which specimens were collected
If IgM test is done: Laboratory results sent < 3 days of receipt of acute blood specimen
If virus isolation is done: results sent < 21 days of receipt of acute blood specimen
If IgG test is done: results sent < 3 days of receipt of convalescent blood specimen
target
> 90%
> 50%1
> 80%
> 80%
> 80%
1 This is the target during non-outbreak periods. Once an outbreak is confirmed, the priority is to
detect and laboratory-confirm outbreaks in neighbouring areas.
PRINCIPAL USES OF DATA FOR DECISION-MAKING
• Investigate suspect cases and collect laboratory specimens to confirm an outbreak and mobilise
emergency immunization activities
• Monitor YF vaccine coverage by geographic region to monitor progress and identify areas of poor
performance so corrective actions can be taken
WHO Recommended Surveillance Standards
October 97
110
SPECIAL ASPECTS
---------------------- -------------------- -------------------- -------------The following 33 countries are at risk for yellow fever epidemics in Africa: Angola, Benin Burkina
Faso, Burundi, Cameroon, Cape Verde, Central African Republic, Chad, Congo, Democratic
Republic of Congo (formerly Zaire), Equatorial Guinea, Eritrea. Ethiopia, Gabon, Gambia Ghana
Guinea. Guinea-Bissau, Ivory Coast, Liberia, Kenya, Mali, Mauritania, Niger. Nigeria, Rwanda,
Senegal, Sierra Leone, Somalia, Sudan, Tanzania, Togo, Uganda.
The following 10 countries are at risk for yellow fever in South America: Bolivia, Brazil, Colombia,
Ecuador, Guyana, French Guiana, Panama, Peru, Surinam, Venezuela.
CONTACT
Regional offices
See Regional Communicable Disease contacts on pages 15-20
Headquarters
Division of Emerging and Other Communicable Diseases, Surveillance and Control (EMC)
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: arthurr@who.ch / outbreakemc@who.ch
Tel: (41 22) 791 2658 / 2850 / 2111
Fax: (41 22) 791 48 78 / 07 46 attn EMC
Global Programme for Vaccines and Immunization (GPV)
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
Tel: (41 22) 791 4405/2111
Fax: (41 22) 791 4193 attn GPV/EPI
WHO Recommended Surveillance Standards
October 97
111
■/
•’
WHO Recommended Surveillance Standards
October 97
.
.i
112
Acute lower respiratory tract infections (aLRTI) and Pneumonia
Acute lower respiratory tract infections (aLRTI)
and Pneumonia
RATIONALE FOR SURVEILLANCE
~
---------------------------Acute lower respiratory infections, of which pneumonia is the most deadly, kills more than 4 million
people a year. The majority of these deaths are among children < 5 years, and ARI are the leading
cause of death in that age group. ARI are a major impact on health services and household income,
accounting for up to 50% of visits by children to health facilities, and are the concition for which
antibiotics are often prescribed and misused world wide. The WHO strategy is to reduce severe
morbidity and mortality through integrated case management of children at primary level in
collaboration with other agencies and governments. Surveillance is necessary to monitor disease
trends and control programmes including essential drug use.
RECOMMENDED CASE DEFINITION
Clinical case definition and classification
PNEUMONIA
Symptoms Cough or difficult breathing and
Signs:
and
breathing faster than 50/min for child 2-12 months
breathing faster than 40/min for child 1-5 years
No chest indrawing, stridor or danger signs
SEVERE PNEUMONIA
Symptoms : Cough or difficult breathing + any danger sign or chest indrawing or stridor
in a calm child.
Danger Signs:
For child 2 months to 5 years
Not able to drink or breast feed, vomits everything, convulsion, lethargic or
unconscious
For child under 2 months
stopped feeding well, convulsions, lethargy or unconscious, wheezing, fever or low
body temperature
Note: Chest indrawing + recurrent wheeze = asthma, probably not pneumonia
RECOMMENDED TYPES OF SURVEILLANCE
--------Routine monthly aggregated reporting from peripheral level to intermediate and central level.
Community surveys/Sentinel surveillance to complement routine data and for evaluation of control
programme activities.
Sentinel surveillance reporting monthly to intermediate and central level.
Quarterly reporting of community/household surveys from peripheral to central level.
RECOMMENDED MINIMUM DATA ELEMENTS
Aggregated data for reporting
Number of cases by age, severity, geographical area, treatment(Y/N), hospitalisation (Y/N),
outcome
WHO Recommended Surveillance Standards
October 97
113
RECOMMENDED DATA ANALYSES, PRESENTATION, REPORTS
Cases/incidence by month, geographical area, age, sex.
Comparisons with same month, age group and geographical area in previous years.
Seasonal and secular data best presented as line graphs.
Annual surveillance summaries should be produced nationally and regionally and fed back. Annual
overview is helpful in trying to identify areas of concern and set priorities.
PRINCIPAL USES OF DATA FOR DECISION MAKING
• Monitor trends in disease incidence
• Monitor treatment guidelines
• Support essential drugs supply
•
Detect peaks in incidence
• Identify high risk areas for further targeting intervention
SPECIAL ASPECTS
ARI is part of the integrated case management approach to child health. The syndromic approach is
recommended as the most effective way to report on cases. However from the perspective of
surveillance of diseases this approach has not been proven. Multiple diagnoses are frequently made
in children. The integrated case management approach may therefore present difficulties for single
disease surveillance.
CONTACT
Regional offices
See Regional Communicable Disease contacts on pages 15-20
Headquarters
Child Health Division (CHD),
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: robinsond@who.ch
Tel: (41 22) 791 2969/2632/2111
Fax: (41 22) 791 4853
WHO Recommended Surveillance Standards
October 97
114
Acute watery diarrhoea
Acute watery diarrhoea (childhood)
RATIONALE FOR SURVEILLANCE
---- ----------------------- -----------One of the major causes of morbidity and mortality in young children, diarrhoeal diseases caused
more than 3 million deaths in 1995 (80% in children under 5 years). About half of these deaths are
due to acute watery diarrhoea. Contaminated food is now thought to be responsible for over two
thirds of cases. WHO supports regional initiatives in co-ordinating activities aimed at improved
preparedness and response to outbreaks of cholera and dysentery. The WHO strategy is to reduce
incidence and fatality through integrated case management in children at primary level in
collaboration with other agencies and governments.
RECOMMENDED CASE DEFINITION
"
- -------------------------- ------Clinical case definition
Acute watery diarrhoea (passage of 3 or more loose or watery stools in the past 24 hours) with or
without dehydration
Laboratory criteria for diagnosis
Laboratory culture of stools may be used to confirm possible outbreaks of specific diarrhoea, but is
not necessary for case definition
Case classification
Not applicable
RECOMMENDED TYPES OF SURVEILLANCE
'
---------------------Patient records should be maintained at peripheral level.
Routine monthly reporting of aggregated data from peripheral level to intermediate and central
level.
Community surveys/Sentinei surveillance to complement routine.data and for evaluation of control
programme activities.
RECOMMENDED MINIMUM DATA ELEMENTS
Case-based data at peripheral level
Unique identifier, age, sex, geographical area
Date of onset
Outcome
Aggregated data for reporting
Number of cases under 5 years by geographical area
Number of deaths under 5 years by geographical area
RECOMMENDED DATA ANALYSES, PRESENTATION, REPORTS
• Number of cases by month, geographical area, agegroup
• Comparisons with same month and geographical area in previous years
• Seasonal and secular data best presented as line graphs
• Monthly surveillance summaries should be produced nationally and regionally and fed back. A
quarterly or annual overview is helpful in trying to identify areas of concern and set priorities
PRINCIPAL USES OF DATA FOR DECISION MAKING
• Monitor trends in disease incidence
• Detect possible outbreak at the local level
• Identify high risk areas for further targeting of intervention
WHO Recommended Surveillance Standards
October 97
115
SPECIAL ASPECTS
Diarrhoeal diseases are part of the integrated case management approach to child health. The
syndromic approach is recommended as the most effective way to report on cases. However from
the perspective of surveillance of diseases this approach has to be proven. Multiple diagnoses are
frequently made in children. This with integrated case management approach may present
difficulties with single disease surveillance.
Dehydration is a useful indicator of acute diarrhoea, and a sudden increase in dehydration in 2 to 5
year old should raise suspicious of a possible cholera outbreak.
The clinical case definition for cholera is:
• In an area where the disease is not known to be present, in a patient aged 5 years or more
severe dehydration or death from acute watery diarrhoea or
• In an area where there is a cholera epidemic, in a patient aged 5 years or more, acute watery
diarrhoea, with or without vomiting.
c
CONTACT
Regional offices
See Regional Communicable Disease contacts on pages 15-20
Headquarters
Child Health Division (CHD),
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: brycej@who.ch
Tel: (41 22) 791 2620/2632/2111
Fax: (41 22) 791 4853
Division of Emerging and other Communicable Diseases, Surveillance and Control (EMC)
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: neiram@who.ch / outbreakemc@who.ch
Tel:(41 22) 791 3977/2660/2111
Fax:(41 22) 791 4198 attn EMC
6
WHO Recommended Surveillance Standards
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116
Acute bloody diarrhoea
Acute bloody diarrhoea (children under 5)
RATIONALE FOR SURVEILLANCE
"
----------------------------Bloody diarrhoea in children is usually a sign of invasive enteric infection that carries a substantial
risk of serious morbidity and death especially in developing countries. Shigella is most frequently
isolated from the stools of affected children. WHO’s policy through the Child Health and
Development division is to promote an integrated affordable approach to the management of the
sick child. The primary objective is to reduce morbidity and mortality.
RECOMMENDED CASE DEFINITION
Clinical case definition
Acute diarrhoea with visible blood in the stool
Laboratory criteria for diagnosis
Laboratory culture of stools may be used to confirm possible outbreaks of specific diarrhoea, but is
not necessary for case definition
Case classification
Not applicable
RECOMMENDED TYPES OF SURVEILLANCE
Patient records should be maintained at peripheral level.
Routine monthly reporting of aggregated data from peripheral level to intermediate and central level.
Community surveys/Sentinel surveillance to complement routine data and for evaluation of control
programme activities
Note:
Laboratories involved in diagnosis of Shigella dysenteriae type 1 should report confirmed
cases including zero reporting.
RECOMMENDED MINIMUM DATA ELEMENTS
Case-based data at peripheral level
Unique identifier, age, sex, geographical area
Date onset, date treatment
Treatment given (Y/N), kind of treatment
Hospitalised(Y/N)
Outcome
Aggregated data for reporting
Number of cases < 5 years by geographical area
Number of deaths < 5 years by geographical area
RECOMMENDED DATA ANALYSES, PRESENTATION, REPORTS
• Number of cases by month, geographical area, age group
• Comparisons with same month and geographical area in previous years
• Seasonal and secular data (best presented as line graphs)
• Monthly surveillance summaries should be produced nationally and regionally and fed back
• A quarterly or annual overview is helpful in trying to identify areas of concern and set priorities
WHO Recommended Surveillance Standards
October 97
117
PRINCIPAL USES OF DATA FOR DECISION MAKING
• Monitor trends in disease incidence
• Identify high risk areas for further targeting of intervention
SPECIAL ASPECTS
A national reference laboratory is needed to confirm outbreaks of S. dysenteriae type 1 where
suspected. The syndromic approach, while important in the case management in the primary care
setting may not lend itself to surveillance of specific diseases. •
CONTACT
Regional offices
See Regional Communicable Disease contacts on pages 15-20
Headquarters
Child Health Division (CHD),
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: brycej@who.ch
Tel: (41 22) 791 2620/2632/2111
Fax: (41 22) 791 4853 attn CHD
Division of Emerging and other Communicable Diseases, Surveillance and Control (EMC)
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: neiram@who.ch / outbreakemc@who.ch
Tel:(41 22) 791 3977/2660/2111
Fax:(41 22) 791 4198 attn EMC
WHO Recommended Surveillance Standards
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118
Sexually transmitted diseases (Genital ulcer syndrome)
Sexually transmitted diseases
(Genital ulcer syndrome)
RATIONALE FOR SURVEILLANCE: ---------------------------- ------------------------------------------------- The morbidity attributable to STD, relative to that caused by other infectious diseases has
continued to increase throughout this century. STD's now rank among the five most important
(inclXc EST7 pr°dUCtiVe
lost ln ^veloping countries. Sexually transmitted diseases
( c udmg HIV/AIDS) are seen more often as disease syndromes. WHO's approach to the control
STD s revolves around integrated primary health care at an early stage.
W6 USB a syndromic definition, which can be used to monitor the incidence of a number of
Lvmnhnntn ?ncro'd (HaemoP/7'^s ducreyi), Herpes simplex, Syphilis (Treponema pallidum)
Lymphogranuloma venereum, Chlamydia trachomatis, Donovanosis.
RECOMMENDED CASE DEFINITION
- -------------------------------------------------------Clinical case definition
Genital ulcer pain on penis or scrotum in men and on labia, vagina or cervix in women with or
witnout inguinal adenopathy
Laboratoiy criteria for confirmation
Laboratory confirmation of organism if possible but this is not necessary for the case definition
Case classification
Not applicable
RECOMMENDED TYPES OF SURVEILLANCE
-------------------------- —
Routine monthly reporting from sentinel sites on aggregated or case-based data to intermediate
Annual reports from sentinel sites to central level.
>
In some countries surveillance for genital ulcer relies on specific surveys.
RECOMMENDED MINIMUM DATA ELEMENTS
Case-based data for reporting
Unique identifier, age, sex, geographical area
Date of onset
Laboratory results
----------- --------------
Aggregated data for reporting
Number of cases by agegroup, geographical area
RECOMMENDED DATA ANALYSES, PRESENTATION, REPORTS----------------------------------• Syndromic cases/incidence by month, geographical area, agegroup, sex, laboratory results
• Compansons with same month, age group and geographical area in previous years
• An annual overview is helpful in trying to identify areas of concern and to set priorities
WHO Recommended Surveillance Standards
October 97
119
PRINCIPAL USES OF DATA FOR DECISION MAKING
• Surrogate indicator for incidence of chancroid and primary syphilis
• Estimate importance of genital ulcer in men and women - frequency and distribution of disease
• Monitor trends over time
•
Define resources, supplies for service, prevention and control measures
• Raise awareness in policy makers and communities
• Identify high risk areas for further targeting intervention
• Define and monitor effective diagnostic and therapeutic procedures
• Monitor and improve existing programme keeping it relevant and effective
SPECIAL ASPECTS
None
CONTACT
Regional offices :
See Regional Communicable Disease contacts on pages 15-20
Headquarters:
Office of H1V/AIDS and Sexually Transmitted Diseases (ASD)
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: gerbasea@who.Qh
Tel: (41) (22) 791 4658 /2111
Fax: (41) (22) 791 4834 attn ASD
J
WHO Recommended Surveillance Standards
October 97
120
Sexually transmitted diseases (Urethral discharge syndrome)
Sexually transmitted diseases
(Urethral discharge syndrome)
RATIONALE FOR SURVEILLANCE
--------------------------------------------------- ----The morbidity attributable to STD, relative to that caused by other infectious diseases has
continued to increase throughout this century. STD’s now rank among the five most important
causes of years of heaithy productive life lost in developing countries. Sexually transmitted diseases
(including HIV/AIDS) are seen more often as disease syndromes. WHO's approach to the control
STD s revolves around integrated primary health care at an early stage.
We use a syndromic definition, which can be used to monitor the incidence of a number of
conditions mainly gonococcal and non-gonococcal urethritis
RECOMMENDED CASE DEFINITION
Clinical case definition
Urethral discharge in men with or without dysuria
Laboratory criteria for diagnosis
Laboratory confirmation of organism if possible but this is not necessary for the case definition
(Gram stain to look for intracellular dipplococci).
Case classification
Not applicable
Note : Gonorrhoea and Chlamydia are the main causes of urethritis among male clinic attenders in
most developing countries. Although gonococcal urethritis tends to be more purulent and
non-gonococcal urethritis more mucoid these signs are not discriminatory in field conditions.
RECOMMENDED TYPES OF SURVEILLANCE
"
'—------- - ----Routine monthly reporting from sentinel sites of aggregated data to intermediate level.
Annual reports from sentinel sites to central level.
In come countries surveillance for urethral discharge relies on specific site surveys (STD clinics).
RECOMMENDED MINIMUM DATA ELEMENTS
Case-based data for local record
Unique identifier, age, sex, geographical area
Date of onset
Laboratory results
’
Aggregated data for reporting
Number of cases by age group, geographical area
Number of cases treated
RECOMMENDED DATA ANALYSES, PRESENTATION, REPORTS
“
Syndromic cases/incidence by month, geographical area, agegroup, sex, laboratory results.
Comparisons with same month, age group, laboratory results and geographical area in previous
years
An annual overview is helpful in trying to identify areas of concern and to set priorities.
Secular data best presented as line graphs.
PRINCIPAL USES OF DATA FOR DECISION MAKING
• Monitor trends in disease incidence
• Identify high risk areas for further targeting intervention
WHO Recommended Surveillance Standards
October 97
121
SPECIAL ASPECTS
Culture of N. gonorrhoeae is not essential for diagnosis and clinical management.
Treat all cases for gonorrhoea and non gonococcal urethritis (NGU) or do gram stain: if no
intracellular dipplococci treat for NGU
CONTACT:
Regional offices :
See Regional Communicable Disease contacts on pages 15-20
Headquarters:
Office of HIV/AIDS and Sexually Transmitted Diseases (ASD)
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: gerbasea@who.ch
Tel: (41) (22) 791 4658 /2111
Fax: (41) (22) 791 4834 attn ASD
»
WHO Recommended Surveillance Standards
October 97
122
Sexually transmitted diseases (Vaginal discharge syndrome)
Sexually transmitted diseases
(Vaginal discharge syndrome)
RATIONALE FOR SURVEILLANCE
-- -------------------------The morbidity attributable to STD, relative to that caused by other infectious diseases has
continued to increase throughout this centu^. STD's now rank among the five most important
causes of years of healthy productive life lost in developing countries. Sexually transmitted diseases
Oncludmg HIV/AIDS) are seen more often as disease syndromes. WHO's approach to the control
STD s revolves around integrated primary health care at an early stage.
RECOMMENDED CASE DEFINITION
~
~
Clinical case definition and recommended case definition WHO
Abnormal vaginal discharge (amount, colour and odour) with or without lower abdominal pain or
specific symptoms or specific risk factor (without speculum)
Laboratory criteria for diagnosis
Laboratory confirmation of organism if possible but this is not necessary for the case definition
(organism isolation)
Case classification
Not applicable.
RECOMMENDED TYPES OF SURVEILLANCE
“
-- ------------------Routine monthly reporting from sentinel sites of aggregated data to intermediate level.
Annual reports from sentinel sites to central level.
In come countries surveillance for vaginal discharge relies on specific site surveys (STD clinics) and
on community surveys.
RECOMMENDED MINIMUM DATA ELEMENTS
Case-based data for local records and contact tracing
Unique identifier, age, sex, geographical area
Date of onset
Treatment (Y/N)
Risk factors
Contacts
Aggregated data for reporting
Number of cases treated for vaginitis
area b6r °f 03565
a9e9rOup' laboratorY diagnosis, severity (PIO or no PID), geographical
RECOMMENDED DATA ANALYSES, PRESENTATION, REPORTS
---------------------------• Number of cases by month, geographical area, agegroup, sex
• Comparisons with same month, age group and geographical area in previous years
•
Monthly surveillance summaries should be produced nationally and regionally and fed back
• A quarterly or annual overview is helpful in trying to identify areas of concern and set priorities
WHO Recommended Surveillance Standards
October 97
123
9
PRINCIPAL USES OF DATA FOR DECISION MAKING
• Monitor trends in disease incidence
• Identify high risk areas for further targeting intervention
SPECIAL ASPECTS
Risk factors are region/country specific and are not universal.
CONTACT
Regional offices :
See Regional Communicable Disease contacts on pages 15-20
Headquarters:
Office of HIV/AIDS and Sexually Transmitted Diseases (ASD)
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: gerbasea@who.ch
Tel: (41) (22)791 4658/2111
Fax: (41) (22) 791 4834 attn ASD
WHO Recommended Surveillance Standards
October 97
124
Antimicrobial resistance
No specific ICD-10 code
Antimicrobial resistance
RATIONALE FOR SURVEILLANCE
“
---------------------------------Antimicrobial resistance has increased dramatically in the last decade adversely affecting control of
many important diseases including Shigella dysentery, pneumonia, TB, and malaria. Antimicrobial
resistance leads to prolonged morbidity, increased case fatality and lengthens duration of
epidemics. Surveillance is necessary for national and international co-ordination and collaboration in
issues relating to antimicrobial use and resistance and drug development.
RECOMMENDED DEFINITION
-- ---------------------------------------------- - -------Microbial isolate that is resistant to one or more antimicrobial agents on standard susceptibility tests
(e.g. disk diffusion, minimal inhibitory concentration determination)
RECOMMENDED TYPES OF SURVEILLANCE
- -------------------- -----Peripheral level
Every hospital should have a surveillance system for antimicrobial resistance. This should involve
collaboration between microbiologists, clinicians, pharmacists, and infection control personnel.
Intermediate/Central level
• At minimum reporting from sentinel sites should occur
• Surveillance should be geographically and demographically representative
• Routine laboratory-based reporting (this may include comprehensive reporting of aggregate
statistics as well as case-based reporting from sentinel sites)
• Reporting should be at least once a year
• Collection and confirmation of new or unusual resistance phenotypes should also be performed
by reference authorities
RECOMMENDED MINIMUM DATA ELEMENTS
Case-based data at peripheral level and sentinel sites
Unique identifier, age, sex
Hospitalised (Y/N)
Specimen type, specimen date, organism, microbial susceptibility test results
Aggregated data for reporting
Distribution by type (resistant intermediate, susceptible)
Number tested for each organism by antibiotic
Aggregate statistics should address important local and national antimicrobial resistance problems.
Statistics for many important pathogens should be reported separately for hospitalised and non
hospitalised cases, as well as by age group.
RECOMMENDED DATA ANALYSES, PRESENTATION, REPORTS
At peripheral level
Daily review for unusual or important results
Weekly-to-monthly review of organism frequencies and resistance profiles for outbreaks
Quarterly review of data for monitoring resistance trends and review of hospital usage policy
At intermediate and central level
Aggregate data
• Quarterly review of data for monitoring of resistance trends by organism, antibiotic, geographic,
and demographic parameters.
WHO Recommended Surveillance Standards
October 97
125
• Quarterly review of resistance results for possible errors in laboratory performance
Case-based data
Same analyses as for aggregate statistics, as well as more detailed analyses on test performance,
mechanisms of resistance, and strain epidemiology
PRINCIPAL USES OF DATA FOR DECISION MAKING
• Monitor the changing trends and issues in antimicrobial resistance
• Aid the development of antimicrobial usage and infection control policies
• Monitor the impact of antimicrobial usage and infection control policies
• Guide the establishment of priorities for the development of new antimicrobial agents
• Aid research activities in the development of new antimicrobial agents
• Monitor outcome of treatment
<
SPECIAL ASPECTS
National Quality Assurance Programmes improve test performance by laboratories in the provision
of reliable results to clinicians
Local and national uses of antimicrobial resistance data can be greatly enhanced by the use of
specialised software, such as WHONET, available free of charge from the WHO
CONTACT
Regional offices:
See Regional Communicable Disease contacts on pages 15-20
Headquarters
WHO Division of Emerging and other Communicable Diseases Surveillance and Control (EMC)
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: amr@who.ch / outbreakemc@who.ch
Tel: (41 22) 791 2660/2111
Fax: (41 22) 791 4878 / 0746 attn EMC
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Anti-tuberculosis drug resistance
No specific ICD-10 code
Anti-tuberculosis drug resistance
RATIONALE FOR SURVEILLANCE
------------------------------------------------- —
Resistance of the tubercle bacilli to antimycobacterial agents is an increasing problem world-wide The
true magnitude of the problem has not been adequately surveyed. Drug-resistant TB, particularly
multi-drug resistant TB (MDR-TB) is a major potential threat to TB control because only a few drugs
are effective and available against Mycobacterium tuberculosis, especially in low-income countries.
RECOMMENDED CASE DEFINITION
--------------------------------------- - —
Anti-TB drug resistance occurs when a bacterial isolate is resistant to one or more antimicrobial
agents on internationally recommended methods for susceptibility tests (e.g. the economic variant of
the proportion method, using Lowenstein-Jensen medium). The absolute concentration, resistance
ratio, and other standardised methods may be used.
Primary drug resistance is defined as the presence of resistant strains of M. tuberculosis in a patient
who, in response to direct questioning, denies having had any prior anti-TB treatment or where in
countries were adequate documentation exists, no documented evidence of such a history is found.
Acquired drug resistance is defined as the presence of resistant strains of M. tuberculosis in a
patient who, in response to direct questioning, admits having had prior anti-TB treatment or where , in
countries were adequate documentation exists, documented evidence of such a history is found.
RECOMMENDED TYPES OF SURVEILLANCE
‘
Three main principles must be followed:
1. Use of a data collection system (based on standard registers) for all TB patients, designed in
such a way that new patients are distinguished from those previously treated. National TB
Programmes using the WHO TB control strategy adopt a recording and reporting system which
allows this kind of differentiation.
2.
Use of laboratory methods internationally recommended for susceptibility testing. A country should
have no more than one national reference laboratory (NRL) to*which diagnostic centres send the
sputum (with the exception of very large countries). The NRL should be linked to an international
laboratory by strain exchange to ensure quality control.
3.
Adequate sampling strategies which ensure the representativeness of the country or area to be
surveyed.
In general, countries can choose
<‘
between routine surveillance and ad hoc surveys at regular intervals
(3-5 years) according to the availability of resources, logistics, and operational considerations.
RECOMMENDED MINIMUM DATA ELEMENTS
"
----Peripheral level (diagnostic centres)
Patient identifier, age, sex, specimen date, history of previous treatment, other data (nationality
HIV) Only sputum smear positive patients should be enrolled
National Reference Laboratory
Anti-TB drug susceptibility test results
Central
Data from the diagnostic centres and from the NRL should be matched and analysed by a co
ordinating team
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RECOMMENDED DATA ANALYSIS, PRESENTATION, REPORTS
Peripheral level(diagnostic centres)
The data should be tabulated at regular intervals by the diagnostic centres and the NRL, using
standard forms or be extracted from routine registers.
Central level
Based on the information provided by the diagnostic centres, the national co-ordinating team must
make regular reports to the heads of the NTP and the reference laboratory.
Data must be analysed, whenever feasible, by computer (WHO developed a software based on
EPI Info).
Analysis must be done on a yearly basis for routine surveillance or at the end of ad hoc surveys.
Data must be aggregated by level of resistance to each single drug and each single combination
of drugs as well as between primary and acquired resistance.
Stratification of data by age, gender, etc. and trend analysis may be done when necessary.
PRINCIPAL USES OF DATA FOR DECISION-MAKING
• Monitor levels and trends of anti-TB drug resistance prevalence as an indicator of the
effectiveness of TB control efforts
• Identify outbreaks of multi-drug resistance in certain settings
• Provide feedback to those regions or areas which participated in region-representative surveys
• Under special circumstances, review the policy of TB case management
SPECIAL ASPECTS
National quality assurance programmes to assure that the performance of each NRL is being
monitored by an international laboratory network.
Reporting to WHO for international comparison of performance.
WHO set up a global network of supra-national reference laboratories (SRL) which are responsible for
quality control in various countries. In addition, they exchange strains amongst themselves. This
quality assurance allows for the international comparison of survey results.
WHO produced a simple software programme based on EPI Info for entering and analysing data from
surveys. It can produce summary tables with the prevalence of drug resistance for each drug,
analysed from different perspectives.
CONTACT
Regional Offices
See Regional Communicable Disease contacts on pages 15-20
Headquarters
WHO Global Tuberculosis Programme
TB Research and Surveillance Unit
20, Avenue Appia, CH-1211 Geneva 27 Switzerland
E-mail address: raviglioneM@who.ch
Tel: (41)22 791 2663
Fax: (41)22 791 4199
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Foodborne diseases
Foodborne diseases
RATlONALE FOR SURVEILLANCE
- ---------- --------------------------A foodborne disease is a disease, usually either infectious or toxic in nature, caused by agents that
enter the body trough ingestion of food or drinking-water. In addition to diseases mentioned in the
manual (e.g. salmonellosis, cholera, shigellosis, hepatitis A...) surveillance of other foodborne
diseases could be carried out. The surveillance helps to determine the magnitude and trend of
foodborne diseases and to monitor and evaluate food safety.
Surveillance is also needed for early detection and control of outbreaks, and identification of risk
factors, as well as planning and evaluation of interventions.
RECOMMENDED CASE DEFINITION
Clinical case definition
The clinical case definition varies with the specific disease
Laboratory criteria for confirmation
Isolation of pathogen
Case classification
Suspected:
A case that meets the clinical case definition of a specific foodborne disease
Probable:
Not applicable
Confirmed:
A suspected case in whom laboratory investigation confirms the presence of one or
more foodborne pathogens in a clinical specimen
Outbreak:
An incident in which two or more persons experience a similar illness after what is
thought to have been a common exposure (ingestion of the same food or ingestion
of water of the same source)
2
RECOM MENDED TYPES OF SURVEILLANCE
------------------------Parallel systems of surveillance may be used, depending on specific surveillance objectives
• Routine immediate reporting of case-based data on suspected cases form peripheral level to
intermediate level (notifications). Routine weekly reporting of aggregated data on suspected and
confirmed cases from peripheral to intermediate and central level
• Routine weekly case-based or aggregated reporting from laboratories on confirmed cases to
intermediate and central level
• Sentinel surveillance (utilising reporting physicians or laboratories)
• Community studies
Sentinel surveillance or community studies can provide more detailed epidemiological and
microbiological information. These systems may give a better picture of the true incidence and
impact of disease in a defined population. However they are likely to miss outbreaks and as such do
not represent a valid approach to outbreak detection.
All outbreaks should be investigated and notified to the intermediate and central level.
nternational: All major foodborne disease outbreaks, particularly those implicating a commercial
product, should be reported to the Programme of Food Safety and Food Aid, WHO
(Global databank on foodborne diseases (notified cases); global databank on
foodborne disease outbreaks (under development), and regional programmes for
surveillance of foodborne diseases).
Note : A minimum data set should be collected on each outbreak at intermediate and central level.
This should be done after the outbreak investigation and should include key variables
describing the nature and extent of the outbreak.
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RECOMMENDED MINIMUM DATA ELEMENTS
Case-based data at peripheral level
Case classification (suspected/confirmed)
Unique identifier, age, sex, geographical information
Date of onset, diagnosis, travel history
Suspected food, where purchased, prepared, consumed
Aggregated data for reporting
Number of cases by age group, sex, geographical area, week.
Case-based data from laboratory
Unique identifier, age, sex, geographical information
Date of onset, date of specimen
Specimen type, organism(s) identified.
Aggregated data from laboratory
Number of cases by age group and sex, by geographical area, by week, by organism.
Outbreaks aggregated data:
Number of people at risk/ill/hospitalised/dead
Geographical information, outbreak setting (e.g. restaurant, hospital, school)
Date of first and last case
Food or constituent implicated, causal agent
Contributing factors (e.g. storage, heating, cross-contamination, food handler, environment)
RECOMMENDED DATA ANALYSES, PRESENTATION, REPORTS
Surveillance data
Frequent review of clinical and laboratory data looking for clusters of cases in time, place or
person. All suspected clusters should be investigated to establish whether an outbreak has
occurred
Incidence of disease notifications and laboratory identifications by week, geographical area,
organism, age group and sex (map incidence by geographical area if possible)
Outbreak investigation data
Incidence of outbreaks by month, geographical area, setting of outbreak, causal agent, attack
rate, duration of outbreak, foods implicated and factors contributing to the outbreak.
PRINCIPAL USES OF DATA FOR DECISION MAKING
• Determine the magnitude of the public health problem
• Detect clusters/outbreaks on time
• Track trends in foodborne disease over time
• Identify high-risk food, high-risk food practices and high-risk pbpulations for specific pathogens.
• Identify emergence of new pathogens
• Guide the formation of food policy and monitor the impact of control measures
• Assess risk and set standards
•
Provide information to enable the formulation of health education in food safety
See also “Surveillance of foodborne diseases: What are the options” Food safety unit WHO
SPECIAL ASPECTS
Human surveillance should be linked with food safety and control authorities.
Some diseases (e.g. salmonellosis) have a specific surveillance system which requires reference
laboratories for detailed serotyping.
CONTACT
Regional offices
See Regional Communicable disease contacts on pages 15-20
Headquarters
Programme of Food Safety and Food Aid (FSF)
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail: motarjemiy@who.ch Tel: (41 22) 791 3558/3535/2111 Fax: (41 22) 791 4807 attn FSF
Division of Emerging and other Communicable Diseases, Surveillance and Control (EMC)
20 Avenue Appia, CH-1211 Geneva 27, Switzerland
E-mail : outbreakemc@who.ch
Tel: (41 22) 791 2529/2660/2111 Fax: (41 22) 791 4893
WHO Recommended Surveillance Standards
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ANNEX 1
Surveillance Definitions
Active case-finding The dynamic identification of the occurrence of a disease or health event under
surveillance, (e.g. house visits by community workers to identify cases of tuberculosis).
Active surveillance Routine surveillance where reports are sought dynamically from participants in
the surveillance system on a regular basis (e.g. telephoning each participant monthly to ask about new
cases).
Aggregate surveillance The surveillance of a disease or health event by collecting summary data on
groups of cases (e.g. in many general practice surveillance schemes clinicians are asked to report the
number of cases of a specified diseases seen over a period of time)
Attack rate The proportion of those exposed to an infectious agent who become (clinically) ill.
Case A person who meets the case definition.
Case definition
A set of diagnostic criteria that must be fulfilled to be regarded as a case of a
particular disease. Case definitions can be based on clinical criteria, laboratory criteria or a
combination of the two.
Case classification Gradations in the likelihood of being a case (e.g. suspected/probable/confirmed).
This is particularly useful where early reporting of cases is important (e.g. Ebola haemorrhagic fever)
and where there are difficulties in making definite diagnoses (e.g. specialised laboratory tests
required).
Case-based surveillance The surveillance of a disease by collecting specific data on each case (e.g.
collecting details on each case of Acute Flaccid Paralysis in polio surveillance)
*
Case fatality rate The proportion of people who die as a proportion of all cases. This will vary
depending on the case definition used.
Cluster The occurrence of an unusual number of cases in person, place or time.
Community surveillance Surveillance where the starting point is a health event occurring in the
community and reported by a community worker or actively sought by investigators. This may be
particularly useful during an outbreak and where syndromic case definitions can be used, (the active
identification of community cases of Ebola virus infection in Kikwit was an example of this type of
surveillance)
Comprehensive surveillance The surveillance of a specified disease or health event in the whole
population at risk for that event, (e.g. AFP surveillance)
Contact An individual who has had contact with a case in a way that is considered to have cause
significant exposure and therefore risk of infection.
Due dates The dates by which reports from a specified period should be received by the each level of
a surveillance system, (used to calculate timeliness)
Endemic The constant presence of a disease within a given geographic area or population group.
Enhanced surveillance
The collection of additional data on cases reported under routine
surveillance. The routine surveillance is a starting point for more specific data collection on a given
health event. This information may be sought from the reporter, the case, the laboratory or from
another surveillance data set.
Epidemic The occurrence of cases of an illness clearly in excess of expectancy. This is often
referred to as an outbreak (more neutral).
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Epidemiological case definition The definition of a case used for reporting to the surveillance
system. The definition may be clinical, laboratory or both. It may relate to a specified disease (e.g.
measles, yellow fever) or may identify a syndrome (e.g. meningitis, AFP)
Exception flagging (reporting) system an automated system of data analysis which calculates
thresholds for unusual events or exceptions.
Exposure Someone who has met with an infectious agent in a way that we from experience know
may cause disease has been exposed.
Feedback The regular process of sending analyses and surveillance reports on the surveillance data
back through all levels of the surveillance system so that all participants can be-informed of trends and
performance.
Health event Any event relating to the health of an individual (e.g. the occurrence of a specific
disease or syndrome, the administration of a vaccine or an admission to hospital)
Hospital surveillance Surveillance where the staring point for a report is the admission of a patient
to hospital with a particular disease or syndrome.
Incidence The number of persons who fall ill with a certain disease during a defined time period
Infectious Disease An illness due to a specific infectious agent or its toxic products that arises
through transmission of that agent or its products from an infected person, animal, or reservoir to a
susceptible host, either directly or indirectly through an intermediate plant or animal host, vector, o r
inanimate environment.
Intensified surveillance The upgrading from a passive to an active surveillance system for a
specified reason and period (usually because of an outbreak). It must be noted that the system
becomes more sensitive and secular trends-may need to be interpreted carefully.
Laboratory surveillance Surveillance where the starting point is the identification or isolation of a
particular organism in a laboratory, (e.g. surveillance of salmonellosis)
Mandatory surveillance A surveillance where participants must report to the system. Notifiable
diseases are one example of a mandatory system where reporting is by law. Another may occur
where for example a heath authority requires all public laboratories to report specified diseases. This
is usually not be law but is linked to their contractual duties.
Notifiable disease A disease that must be reported to the authorities by law or ministerial decree.
Outbreak The occurrence of two or more linked cases of an communicable disease
Passive surveillance Routine surveillance where reports are awaited and no attempt make actively
seek reports from the participants in the system.
Primary care surveillance Surveillance where the staring point for a report is a new consultation for
a particular disease or syndrome with a primary care physician or health worker at a clinic.
Performance indicators Specific agreed measurements of how participants are functioning within
the surveillance system. These indicators may measure both the process of reporting (e.g.
completeness, timeliness) action taken in response to surveillance information (e.g. % cases
investigated) and the impact of surveillance and control measures on the disease or syndrome in
question (e.g. % of outbreaks detected by the system, % drop in cases over a specified time period).
Periodicity The presence of a repeating pattern of excess cases. The repeater can be in
years, months or weeks.
Prevalence The number of persons who have a disease at a specific time
Reporting completeness Proportion of all expected reports that were actually received (usually
WHO Recommended Surveillance Standards
October 97
stated as "% completeness as of a certain date").
Reporting timeliness Proportion of all expected reports that were received by a certain due date.
Reporting system The specific process by which diseases or health events are reported. This will
depend on the importance of the disease and the type of surveillance
Routine surveillance The regular systematic collection of specified data in order to monitor a
disease or health event.
Sentinel surveillance The surveillance of a specified health event in only sample of the population at
risk using a sample of possible reporting sites. The sample should be representative of the total
population at risk.-
Serosurveillance The surveillance of an infectious disease by measuring disease specific antibodies
in a population or sub-population
Surveillance The systematic collection, collation and analysis of data and the dissemination of
information to those who need to know in order that action may be taken.
Surveillance report A regular publication with specific information on the disease under surveillance.
It should contain updates of standard tables and graphs as well as information on outbreaks etc. In
addition it may contain information on the performance of participants using agreed performance
indicators.
Surveillance sensitivity The ability of a surveillance system to detect an outbreak. (The proportion of
all outbreaks that could have been detected by the system)
Surveillance predictive value The likelihood that an “outbreak” detected by a surveillance system is
truly an outbreak
Survey An investigation in which information is systematically collected. It is usually carried out in a
sample of a defined population group and in a defined time period. Unlike surveillance it is not ongoing
though it may be repeated. If repeated regularly surveys can form the basis of a surveillance system.
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Unusual event The occurrence of a disease or health in excess of the expectation. This expectation
is a either a static or dynamic threshold set by the system
Zero reporting The reporting of zero cases when no cases have been detected by the participant.
This allows the next level of the system to be sure that the participant has not sent data that has been
lost or has forgotten to report.
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Software free and in the Public Domain
EPI INFO
WHAT
Epi Info is a series of microcomputer programmes for word processing, data management and
epidemiologic analysis, designed for public health professionals. Epi Info is easy to use, but also offers
programming languages for both data input and analysis so that permanent health information
systems can be developed.
EPI INFO SOFTWARE CONTAINS
Epi Info: this allows rapid set-up of new entry forms and data files, easily customized data entry, and
many data management and analysis techniques.
Epi Map: this displays counts or rates on geographic maps supplied or drawn on the screen. Colours,
shading dots, or noncontiguous cartograms can be used to show any type of numeric data related to
map.
DoEpi: this is a series of educational studies and computer exercises designed to teach both
epidemiology and the use of Epi Info. An instructor’s module is included.
SSS1: this provides functions for Box Jenkins Time Series analysis, “Figure 1” MMWR graphs, robust
trend analysis, and comparison of surveillance data form two sources.
WEBSITES
You can download all the programmes from the Website
CDC Epidemiologic Software (English)
URL (USA): http://www.cdc.gov/epo/epi/software.htm
WHO Homepage WHOSIS (English)
Switzerland: ftp://ftp.unaids.org/inet/ftp/epi/index.html
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Epi Info Manuals from Brixton Books UK (English
URL (UK) http:/mkn.co.uk/help/extra/people/Brixton_ Books
EpiConcept (French)
URL (France): http.//www.epiconcept.fr/epiinfo.html
USD, Inc. (English)
URL (USA): http://www.ULsd-inc.com/phi.html
Epi Info Brazilian Homepage (Portugees)
URL (Brazil): http://www.lampada.uerj.br/epiinfo.html
Epi Info Swedish Homepage (Swedish)
URL (Sweden): http://www.umu.se/socialmedicin/epi/info.htm
Epi Info Norvegian Homepage (Norvegian)
URL (Norway):http://www.gruk.no/epi-info/
Epi Info German Homepage (German)
URL (Germany): http://www.shuttle.de/lga
Epi Info Usergroup BeNeLux (Dutch)
URL (The Netherlands): http://www.inter.NL.net/hcc/Koomen.Em/epinl.html
WHO Recommended Surveillance Standards
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CONTACT
CDC: Andrew G. Dean
The Division of Surveillance and Epidemiology, Epidemiology Program Office
Centers for Disease Control and Prevention (CDC) Atlanta
Georgia 30333
Epi Info Hotline for Technical Assistance
Tel: (404) 728-0545
Fax: (404) 315-6440
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