ICMR BULLETIN VOL. 25-No.-6 & 7-JUNE-JULY-1995.pdf

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ISSN 0377*4910

June-July, 1995

Vol. 25 Nos. 6&7

SUMMARY REPORT OF THE INTERNATIONAL SYMPOSIUM ON
VECTORS AND VECTOR-BORNE DISEASES
Vector-bome diseases constitute a formidable group
among the communicable diseases. According to the latest
report of the World Health Organisation1 infectious and
parasitic diseases accounted for about 32 per cent or over
16 million deaths in 1993. More significantly, in the de­
veloping countries they contribute to 41.5 per cent of
mortality and to over 99 per cent of global deaths. Malaria
is the third most important killer disease with over two
million deaths while leishmaniasis, dengue/dengue
haemorrhagic fever, Japanese encephalitis, lymphatic filariasis
continue to be serious problems in the developing coun­
tries.
In India most of the vector-borne diseases remain
endemic and are major public health concerns. Malaria is
still rampant and is fast spreading with rapid deforestation
and urbanisation which have resulted in a disturbance in
ecological settings of the vector. Both dengue and dengue
haemorrhagic fever have registered a rise in rural as well
as in urban India. Leishmaniasis is a serious cause for
concern, particularly in Bihar and parts of West Bengal,
while the national programme for the control of filariasis
has not yielded the desired results. The lack of effective
drug(s) or a vaccine coupled with the increasing incidence
of resistance shown by both the parasite and the vector.

vector control is increasingly being recognised as the method
of choice for the control of these killer diseases.
Recognising the need to critically look at the magnitude
ofthe problem in a large country like India, the International
Symposium on %ctors and Vector-borne Diseases was
organised by the National Academy of Vector Bome Dis­
eases at The Regional Medical Research Centre (RMRC),
Bhubaneswar, during November 12-15, 1994. The major
objectives of the symposium were : (i) to take stock of the
ongoing research in all the major vector-borne diseases;
(ii) critically look at the present strategies of control and
evaluate their effectiveness; (iii) share experiences with
other researchers working in various parts of India and
abroad in these areas; and (iv) formulate meaningful and
feasible recommendations for the control of the vectorborne diseases in India, and other developing countries.

Summary of Presentations

The four day symposium was attended by over 146
scientists from 40 different institutes in India and abroad.
Papers presented at the symposium covered aspects such
as epidemiology, chemotherapy, immunology, biotechno­
logical considerations, vector biology and ecology, and
control measures for malaria, filariasis, leishmaniasis, aiboviral

Division of Publication & lnformation, ICMR, New Delhi - 1029

diseases, plague and other vector-borne diseases of man and
animals.
Malaria
The symposium took note of the fact that malaria has
returned as a major public health scourge causing enormous
loss to the economy and health of people of India. Malaria
was nearly controlled in the 1960s with DDT spraying.
Now it remains endemic with as much as 9 per cent of
the vector population refractory to insecticide spraying.
There are persistent transmission foci of the disease all over
India, particularly in the urban areas.

Filariasis

A major presentation was on the advances in chemo­
therapy oflymphatic filariasis with diethyl carbamate (DEC)
and ivermectin separately and in combination. There were
also presentations on the natural history and dynamics of
the disease, new diagnostic tools, drug targeting models,
promotion of demand for safe methods to control the disease
like the use of insecticide-impregnated mosquito nets in
tribal belts of Orissa and an overview on the present status
and future of the national filariasis control strategies.
Leishmaniasis

While there was a resurgence of malaria in the 1970s
as evident by its appearance in areas at one time freed of
the disease by the National Malaria Eradication Programme
(NMEP), it was not given sufficient notice. In 1976 an
epidemic situation resulted with the disease returning with
over 6.5 million cases. In 1977, the eradication strategy
was replaced by control under the modified plan of opera­
tion, prioritizing control objectives. In high risk areas spraying
was restarted resulting in an initial decline in the incidence
of malaria stabilizing at about two million cases. Forty per
cent of these cases are due to Plasmodium falciparum, a
dangerous parasite responsible for deaths due to malaria.
Seen in the background of changing malaria profile, return
of malaria has its own characteristic features involving
vector, parasite, host and the environment, establishing new
malaria paradigms. This is facilitated by failures ofcontrol
measures due to blunted control tools aided and abetted by
poor understanding of the malaria transmission dynamics.
Malaria control now requires new approaches and targets,
selective and sustainable vector control, strengthening of
health delivery systems at the periphery, and rapid absorp­
tion ofnew environment-friendly technologies into the National
Malaria Eradication Programme.

Many aspects of this disease were discussed like
immuno-adjuvant activity of positively charged liposomes
towards Leishmania donovani promastigote antigens, elec­
tron transfer system of £. donavani promastigotes,
characterisation of isoenzyme banding patterns of postkala-azar dermal leishmaniasis (PKDL) with respect to L.
donavani and L. tropica, carbamyl phosphate synthetase II
from L.donavani and cultivation of virulent L.donavani
promastigotes in a simplified media.

Other presentations on malaria included investigation
on developing immunogens against ring-infected erythro­
cyte surface antigen (RESA) ofP falciparum, establishing
community demand for insecticide-impregnated mosquito
nets in rural Orissa and a report on knowledge, attitude and
practice (KAP) regarding malaria in tribal areas of
Maharashtra and some desert villages of Rajastan. That
only 4.36% of the respondents in Maharashtra were aware
of the fact that malaria is transmitted with the bite of
mosquitoes once again shows that literacy and awareness
are also critical factors for any efifective malaria control
programme.

Results on several newer class of chemicals and insect
growth regulators like triflumuron were presented. The
symposium was also informed that this insect growth
regulator, known for its larvicidal activity, can also be used
as an adulticide. There were presentations on the natural
history ofthe vectors ofmalaria, filariasis and leishmaniasis,
mechanisms of drug resistance by these vectors and para­
sites, efificacy of spraying of insecticides, biopesticide
formulations as well as other biological control methods.
Many experts also felt that the successful future vector
control strategies would be a judicial combination of both
biological and conventional control methods.

66

Arboviral diseases
A senior WHO official shared the experience of his
group on the new trends in the integrated control of dengue/
dengue haemorrhagic fever (D/DHF) particularly in the
light of global resolution on the prevention and control of
this disease. New findings on entomological studies and
the insecticide susceptibility of vectors of D/DHF - Aedes
aegypti and Culex quinquefasciatus from Bikaner and
Jalore, West Rajastan were also presented and discussed.
Vector biology and control

After a brain stonning session of experts from India
and abroad, there was a general consensus that control of
vector-borne diseases should receive highest priority from
the Government. The symposium also made the following
recommendations:
General Recommendations

1.

For each of these vector-bome diseases, a National
Control Strategy should be refined and/or developed
and implemented taking into consideration recent ex­
periences, ecological changes, technical developments
and newer tools.

2. The system of surveillance and reporting of vectorborne diseases like leishmaniasis, dengue and JE needs
to be improved to obtain reliable and accurate national
level data for building a health management informa­
tion system to monitor seasonal and annual variations
which will facilitate planning strategies for their pre­
vention and control. This activity needs to be inde­
pendent of their control programmes and laboratories/
centres engaged in such activity should be networked.
3. The Government of India may be approached for an
increase in the technical support for diagnosis, man­
agement and treatment of re-emerging diseases by
means of well equipped reference centres, manned by
well trained staff Regional referral centres may be
identified and strengthened for effective diagnostic and
monitoring services.
4. The State Governments should ensure competence and
preparedness of the surveillance component of health
infrastructure in order to forecast epidemics and ensure
the capability of health organisations in containing
outbreaks in the shortest possible time. Regional coordination committees and national level networking
with an apex centre for each disease may yield better
results.
5. Training programmes ofvarious health personnel should
be reoriented to include adequate coverage on the emeiging
diseases.
6. The World Health Organisation and other international
agencies may be requested to assist India to develop
strategies for the prevention and control of resurging
diseases.
7.

In the light of the recent epidemic of plague, the sym­
posium strongly recommended the revival of research

on effective methods ofrodent control as well as improved
methods of monitoring density of rat fleas and their
control, in addition to studies on resistance to com­
monly used insecticides.

8. The symposium appreciated the commendable progress
made in the guinea worm eradication programme and
expressed its support for its complete eradication.

9. In view of growing resistance of vectors to the com­
monly used insecticides like DDT and BHC, the
symposium recommended the use of alternative insec­
ticides including synthetic pyrethroids which are under
the process of registration for public health use in India.
Some recent studies have successfully demonstrated
the usefulness of synthetic pyrethroids in resistance
management among vectors and for self-protection
measures (to be adopted and regularly used by the host)
like impregnated bed nets and other material. Studies
may be carried out to assess the feasibility of using
these tools for managing vector-bome diseases in field
conditions.
10. In view of the introduction of newer insecticides, the
cost effectiveness, social acceptance and safety aspects
of vector control measures should be evaluated in
different settings. Personal protection measures requir­
ing positive health action on a day to day basis need
to be investigated for pin pointing areas for effective
health education.
11. Research Institutes/Centres within th© Indian Council
of Medical Research have shown great potential for
various R&D activities relating to vector biology and
control ofvector-bome diseases like malaria, filariasis,
leishmaniasis, JE and dengue. These Institutes/Centres
should be adequately supported to undertake such activities
including basic research, development of diagnostic
tools, and training. A mechanism may be evolved
where the State Governments may suitably interact and
utilize the expertise available at these Centres.

12. Reorientation programme for in-service personnel may
be taken up to inculcate knowledge regarding newer
contmeasures, diagnostic techniques and strategies
for vector control management. Health education
campaigns may be mounted to transfer skills and
knowledge to the general public regarding various
vector-bome diseases and their prevention. The sym­
posium reiterated the need for community participation
at various stages of vector control, starting from its

67

inception and people should be made active participants
in the management of their health programmes.
Specific Recommendations

Malaria
1.

In the context of the deteriorating malaria situation,
a fresh look must be taken at the existing strategy.

Filariasis
1. The existing national filariasis control strategy should
be carefully analysed and reviewed, taking into con­
sideration guidelines available from global level strat­
egies, especially the use of DEC fortified salt and the
new modified DEC regimens.

2.

2. Research on malaria should receive increasing support
by the Government and wherever needed assistance by
international bodies/agencies be sought to collect fac­
tual data and to develop measures to overcome vector
resistance to insecticides and parasite resistance to
drugs and to study the associated social and cultural
variables to facilitate better management of malaria.
3. It is recommended that in selected areas, biopesti-cides,
environmental control methods and neem oil should be
properly tested on a large scale trial basis by more than
one organisation before introduction into the national
control programmes. Different ecological zones should
be included in these trials, spanning over a period of
3-4 years. These evaluations should include epidemio­
logical assessment of the efiScacy of these newer tools.

Recognising that vector control alone does not reduce
disease morbidity of filariasis at least for some years,
newer vector control tools may be evaluated for their
impact upon disease incidence. These newer tools
include biopesticides, expanded polystyrene beads,
pyrethroid impregnated nets, etc. These trials should
be properly planned and have to be ofprolonged duration
covering 8-10 years period to register any changes in
the incidence of filariasis in children.

References:
1.

The ^brld Health R^oort 1995 - Bridging the Gap. The Warld
Health Organisation, Geneva, 1995

This report has been prepared by Dr A.P. Dash, Assistant
Director, Regional Medical Research Centre, Bhubaneswar and
Dr. K. Satyanarayana, Deputy Director-General, ICMR Headquarters.

ABSTRACTS

Some Research Projects Completed Recently
Phase I trials on intralesional recombinant interferon
gamma in leprosy patients.

infiltration and eiythema were injected with a similar volume
of excipient only as control.

The study was carried out on 66 patients with polar
lepromatous leprosy or borderline lepromatous leprosy to
find out the efficacy of intradermal recombinant interferon
gamma (rlFN-y) and to evaluate the duration, dose and
multiplicity of injections required to induce improvement
in clinical and histological features and bacillary clearance.
The cellular infiltrates were also studied in the biopsies
using immunological markers. After completion of inter­
feron treatment ie 4-6 days later, the patients were given
multidrug therapy (MDT). The MDT was continued
throughout the follow up period. Patients in reaction were
excluded from the study. rlFN-y in 100 pl of excipient was
injected intradermally into well characterised lepromatous
lesions. Contralateral lesions, clinically similar in terms of

rlFN-y proved to have potent effects on the lepromatous
dermal lesions. It had multiple effects, inducing inflamma­
tory responses akin to delayed type hypersensitivity
reaction associated with cell mediated immunity. The
lepromatous skin was found to be capable of mounting an
immunoinflammatory response. There was no defect in
migration of cells nor an irreversible abnormality in the
microenvironment of the bacilliferous granuloma.

68

The studies involving histology, immunochemistry and
ultr&structure gave credance to the fact that multiple cel­
lular and molecular events were initiated by rlFN-y. The
skin induration was due to epidermal thickening resulting
from keratinocyte proliferation and infiltration of T cells

and young monocytes into the dermis. The predominant
lymphocyte was CD4+. Major histocompatibility complex
(MHC) class 2 antigens not only increased on macrophages
but they were newly induced on hitherto negative keratinocytes.
In addition, IP 10, a specific protein induced by IFN-y was
also seen in the skin.
Repeated injections of rlFN-y resulted in a distinct
reduction at 3 weeks ofthe cutaneous load oforganism from
4+ to 5+to 1+to 3+. The disposal of bacilli occurred faster
in the difiused site compared to nodular sites. The immune
induced elimination was rapid and more effective than that
observed by antileprosy drugs alone. It was associated with
activation of macrophages.

The study thus indicated that rlFN-y is a powerful
biological therapeutic for leprosy. Both improvement of
local immunity as well as bacillary elimination were achieved
in two thirds of the patients. Further systemic studies are
required to establish the power of this agent as an adjunct
to MDT in leprosy.

Indira Nath
Department of Biotechnology
All India Institute of Medical Sciences
New Delhi.
Publication:

Strategy for a possible new vaccine against leprosy —
Use of recombinant gene product.

Preparation of monoclonal antibodies to components
of the delipidified cell component (DCC) of Mycobacte­
rium leprae was undertaken. Hybridoma technology was
adopted using spleen cells ofDCC immunised Balb C mice
and SP2 0 myeloma cell lines and 4 monoclonal antibodies
were obtained, showing binding ability to DCC compo­
nents.
Monoclonal antibodies to delipidified cell components
ofM leprae were obtained through hybridoma technique
and two monoclonals with affinity to 38kDa and 65kDa
proteins of DCC have been identified. The other two did
not pick up any specific components in the Western blot.
One monoclonal helped in distinguishing 65kDa of the
cloned protein as being different from the classical heat
shock protein (hsp) of65kDA ofM leprae. The monoclonals
are not specific but show reactivity to some other myco­
bacterial components. The monoclonals can pick up anti­
gens in the sera of lepromatous leprosy patients by ELISA
as distinguishable from sera of normals or patients of
tuberculoid leprosy. Thus the monoclonal antibodies ob­
tained against DCC of M. leprae helped in identifying a
65kDa protein as part of the immunomodulatory compo­
nents.

P.R. Mahadevan
Division of Experimental Biology and Therapy
The Foundation for Medical Research
Bombay.

Sivasai, K.S.R., Prasad, H.K., Misra, R.S., Ramesh, V., Wilfred,
D. and Nath, 1. Effect of recombinant interferon gamma admin­
istration on lesional monocytes/macrophages in lepromatous lep­
rosy patients. Int J Lep 61: 259, 1993.

ICMR NEWS
The following meetings of various technical groups/
committees of the Council were held:

Centre for Advanced Research
in Ocular Infections, New Delhi

Meetings of Scientific Advisory Committees of ICMR
Institutes/ Centres:

Joint Meeting of Regional
Medical Research Centres

June 27-28, 1995
(at Bhubaneswar)

Central Jalma Institute for
Leprosy, Agra

July 12, 1995
(at Agra)

National Institute of Nutrition,
Hyderabad

June 15, 1995
(at Hyderabad)

Laboratory Animal Information
Services Centre, Hyderabad

and
Food and Drug Toxicology
Research Centre, Hyderabad

June 16, 1995
(at Hyderabad)

June 20, 1995
(at New Delhi)

Meetings of Task Forces/Project Review Committees/
Expert Groups held at New Delhi:
Task Force on Management
of Glaucoma

June 6, 1995

69

Project Review Committee for
Projects on Non-Communicable
Diseases

June 7-8, 1995

on key issues in dengue vector control towards the
operationalization of a global strategy, at WHO, Geneva
(June 4-11, 1995).

Expert Group on Scientometric
Studies

July 12, 1995

Dr. Ghafborunissa, Dy. Director, National Institute of
Nutrition, Hyderabad, participated in the II Congress of the
International Society for the Study of Fatty Acids and
Lipids (ISFAL) at Bethesda (June 7-10, 1995).

Participation of ICMR Scientists in Scientific Events:

Dr. R. Prabhakar, Director, Dr. P.R. Narayanan and
Dr. C.N. Paramasivan, Dy. Directors, Tuberculosis Re­
search Centre, Madras, visited Russia for 10 days under
the Indo-Russian Agreement in the Field of Medical Sci­
ences and Public Health (Problem Area — Tuberculosis)
(May 14-23, 1995).

Dr. D.K. Das, Officer-in-Chai^e, Institute of Cytology
and Preventive Oncology, New Delhi, participated in the
XII International Cytology Congress at Madrid (May 2125, 1995).
Dr. V.P. Sharma, Director, Malaria Research Centre,
Delhi, participated in the IX General Assembly of the
Scientific Committee on Problems of the Environment
(SCOPE) at Tokyo (May 28 - June 3, 1995).

Dr. Aurobindo Roy, Asstt. Director, National Institute
of Urology, Pune, participated in the International Con­
gress on Hazardous Waste : Impact on Human and Eco­
logical Health at Atlanta (June 4-8, 1995).
Dr. M.D. Gupte, Oflficer-in-Charge, CJIL Field Unit
at Avadi, Madras, participated in the evaluation of the
leprosy vaccine trial component of the Karonga prevention
study (Malawi leprosy vaccine study) as a member of the
Diagnostic Review Team and Data Monitoring Committee
at Chileumba (Malawi), London and Cambridge (June 423, 1995).
Dr. K.N. Panicker, Dy. Director, \fector Control Re­
search Centre, Pondicherry, participated in the consultation

Dr. G.V Satyavati, Director-General, ICMR, addressed
the state convention on the launching of the Green Health
Movement at the M.S. Swaminathan Research Foundation
at Madras (June 8, 1995).

Dr. P.K. Nag, Asstt. Director, National Institute of
Occupational Health, Ahmedabad, participated in the XII
International Symposium on Night and Shiftwork at Ledyard,
USA (June 13-18, 1995).
Dr. V.P. Sharma participated in the Neem Training
Workshop as a resource person on Neem and Malaria
Control at Mbita, Kenya (June 20-21, 1995).
Dr. N.V. Giridharan, Senior Research Officer, Labo­
ratory Animal Information Services Centre, Hyderabad,
participated in the International Conference on Frontiers in
Laboratory Animal Sciences at Helsinki (July 2-6, 1995).

Dr. B. Dinesh Kumar, Research Officer, Food and Drug
Toxicology Research Centre, Hyderabad, participated in
the VII International Congress of Toxicology at Seattle
(July 2-6 1995).
Dr. G.V. Satyavati participated in the XVIII Session
ofthe Joint Co-ordinating Board ofthe UNDP/World Bank/
WHO Special Programme for Research and Training on
Tropical Diseases at Luxembourg (July 3-5, 1995).

Dr. Srikant Tripathy, Sr. Research Officer, National
AIDS Research Institute, Pune, participated in a meeting
on HTV Vaccine for Developing Countries at Boston (July
10-13, 1995).

COUNCIL'S TRAINING PROGRAMMES FOR 1995-96
Virology

•

Training Course on Techniques in Neuroendocrine Re­
search (February 6-10, 1996).

At the National Institute of Virology, Pune:
Diploma in Medical Urology (June 1995 - May 1996).,

•

Endocrinology
Reproductive Biology

At the Institute for Research in Reproduction, Bombay:
・

Training Course on Techniques in Immunology, Cell
• Biology and Molecular Biology (November 2-25,1995).

70.

At the National Institute of Nutrition, Hyderabad:
•

Arnual Training Course on Endocrinological Tech­
niques and their Application (August/September, 1995).

Nutrition

Medical Entomology

At the National Institute ofNutrition, Hyderabad:

/f the Vector Control Research Centre, Pondicherry:

•

M.Sc. in Applied Nutrition (June 1, 1995 - February
28, 1996).

•

Annual Training Course in Nutrition (December 1,
1995 - February 28, 1996).

Laboratory Animal Technology
At the Laboratory Animal Information Services Centre,
National Institute ofNutrition, Hyderabad:

Oncology

•

Training Course for Laboratory Animal Technicians
(June - July, 1995).

•

Training Course for Laboratory Animal Supervisors
(September 4 - November 30, 1995).

At the Institute of Cytology and Preventive Oncology,
New Delhi:

•

M.Sc. in Medical Entomology (From August 1995: for
2 years).

•

Workshop on Molecular Biology ofMruses and Cancer
alongwith Oligo DNA Synthesis and Polymerase Chain
Reaction (September 18-22, 1995).

Haematology
At the Institute ofImmunohaematology, Bombay:

Occupational Health
At the National Institute of Occupational Health,
Ahmedabad:

•

Training Course in Blood Group Serology and Blood
Bank Methodology for Medical Officers (August 1 September 29, 1995).

•

Orientation Course on Occupational Health for Indus­
trial Medical Officers (November 13-24, 1995).

•

Training Course in Blood Group Serology and Blood
Bank Methodology for lechnicians (August 1-31,1995).

•

Training Course on Air Pollution Monitoring and Risk
Assessment (December 13-19, 1995).

•

Training Course in Advanced Haematology and
Immunohaematology (September 11-29, 1995).

ERRATUM
Article entitled “AIDS and the Family” November-December, 1994, vol. 24, page 127, para 6,
lines 20-24 : "If for any .reason.............. bleach solution
'
*
should read as follows:
"If for any reason disposable syringes and needles are used, needles should not be recapped/bent/
broken/removed from disposable syringes or otherwise manipulated by hand. After use, the syringe with
needle and other sharp instruments should be placed in puncture proof containers and incinerated. If
the ^cility for incineration is not available, hypochlorite or other suitable disinfectant should be aspirated
into the syringe and then the syringe and attached needle should be immersed in disinfectant solution
for 30 minutes'
.
*

71

EMERITUS MEDICAL SCIENTISTS

INDIAN COUNCIL OF MEDICAL RESEARCH
Nominations/applications are invited from distinguished retiring Scientists engaged in research in
the field of biomedicine for consideration for appointment as Emeritus Medical Scientists under the
Council. Full particulars can be obtained from the office of the Director-General, (Personnel Section),
Indian Council of Medical Research, Post BoxNo.4911, New Delhi-110029. Scientists who have retired
or are going to retire upto 31st March, 1996 may apply for the appointment as Emeritus Medical Scientist
under the Council.
Last date for receipt of applications is 30th September, 1995.

Editorial Board
Chairperson

Members

Dr. G.V. Satyavati
Director-General

Dr. Badri N. Saxena
Dr. C.R. Ramachandran

Editor
Dr. N. Medappa

Printed and Published by Shri J.N. Mathur for the Indian Council of Medical Research, New Delhi
at the ICMR Offset Press, New Delhi-110029
R.N. 21813/71

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