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Two species namely Wuchereria bancrofti and Brugia malayi
are prevalent in India
and the former contributes 99.4 % problem in the country. In mainland India,
the microfilariae (mf) exhibit nocturnal periodicity, necessitating night
blood surveys between 8.00 pm
and 12 midnight to detect
mf carriers. Subperiodic form of W.bancrofti was detected among aborigines
inhabiting a few islands of Nicobar
group of islands.
W.bancrofi infection has been showing increasing trend
during the last five decades. During 2001, it was estimated that 473 million
population (348 million in rural and 125 million in urban areas are exposed to the risk of infection.
About 31 million mf carriers and 23 million disease cases are estimated to be
living in 20 endemic States/UTs in the country.
After pilot project in Orissa from 1949 to 1954, the
National Filaria Control Programme (NFCP) was launched in the country in 1955
with the objective of delimiting the problem, to undertake control measures
in endemic areas and to train personnel to man the programme. The main
control measures were mass DEC administration, antilarval measures in urban
areas and indoor residual spray in rural areas. NFCP was assessed in 1960
which revealed the failure of mass DEC administration due community
non-cooperation and ineffectiveness on insecticidal indoor spray due to high
resistance in vector. The programme was withdrawn from rural areas while in
urban areas, antilarval measures continued to be the main control method. The
First Assessment Committee recommended reorganisation of control units on the
basis of population and establishment of new control units. The Assessment
Committee in 1970 recommended selective mf carrier treatment at a dose of 6
mg/kg per day for 12 days as a compliment to antilarval measures,
delimitation of the problem in unsurveyed districts and regionalisation of
control measures in contiguous areas. The Third Assessment in 1982
recommended extension of NFCP to rural areas through primary healthcare
system with 100% Central assistance for material & equipment, undertaking
DEC medicated salt regimen in high endemic districts and control of B.malayi
infection. The Fourth Assessment in 1995 recommended integrated vector
control measures, implementation of model bye-laws in towns, new technique on
detection of mf carriers and fresh delimitation surveys.
The programme component of NFCP was transferred from NICD
to NAMP in 1978 while research and training components were retained with
NICD. Presently, the programme covers 53 million people (about 11% of endemic
population) through 206 control units and 198 filaria clinics in 18 of the 20
endemic States/UTs. The delimitation surveys are conducted by 27 survey units
in these States. During Fourth Five Year Plan the NFCP was 100 per cent
Centrally sponsored programme. But in Fifth Five Year Plan, only material and
equipment were supplied by the Centre and the entire operational cost was
borne by the States. However, from 1978 onward the Central assistance was
further reduced by sharing the cost of
material and equipment on 50:50 basis. Up to Seventh Five Year Plan the NFCP
budget was separate and the same was merged with budget of Urban Malaria
Scheme during Eighth Five Year Plan continuing the sharing the cost of
material and equipment on 50:50 basis between the Centre and the States. The
organophosphorus compounds like temephos and fenthion and drugs are supplied
by the Centre while MLO, etc. are procured by the States.
Medicated salt regimens in India during 1968-69 showed very
encouraging results in pilot trials in the Uttar Pradesh and Andhra Pradesh.
The distribution of 0.1% DEC medicated salt to general public for one year
was implemented in Lakshadweep, comprising a
population of 25,000 during 1976-77 which reduced mf rate by 80% and
circulating mf by about 90%. The DEC medicated salt project with 0.2%
concentration was concluded at Karaikal, Pondicherry which gave 98% reduction in mf.
B.malayi control undertaken as a pilot project under the
auspices of NICD in Kerala has revealed that the vectors of B.malayi are
amenable to indoor residual spray of HCH at a dose of 0.2 g/m2 per round,
three rounds a year. Integrated vector
control approach for control of this infection is being implemented by VCRC
Pondicherry in Shertally Taluk of Ernakulum
district, Kerala.
Revised Strategy for the control of Lymphatic Filariasis
in India was launched in
1996-97 in 13 districts in seven endemic states namely Andhra Pradesh, Bihar,
Kerala, Orissa, Uttar Pradesh, Tamil Nadu and West
Bengal, where Mass Drug Administration was undertaken. These
seven States contribute over 86% of mf carriers and 97% of disease cases in
the country. The main strategy comprises of:
 single day mass therapy at a dose of 6 mg/kg
body wt annually,
management of acute and chronic filariasis
through referral services at selective centres,
IEC for inculcating individual/community based
protective and preventive measures for filaria control,
antivector measures to continue in all the
NFCP towns as complimentary to antiparasitic measures and mf carriers
detected in filaria clinics and elsewhere to receive the standard dose of 6
mg/kg body wt. per day for 12 days.
For the management of acute and chronic filariasis, the
actions envisaged are:
adequate referral centers for filaria case
management to be developed in selected centres initially which would be
extended to other areas.
treatment of adenolymphangitis (ADL) with
antibiotics to be augmented since majority of acute episodes appear to be of
bacterial aetiology,
rigorous local hygiene measures with or
without local antibiotic and antifungal agents to be promoted to prevent ADL
so as to permit the reversal of lymphoedema,
early treatment with standard 12-day therapy
of mf carriers to be adopted to prevent further lymphatic damage and renal
failure,
community health education on the importance
of local hygiene to the affected to be intensified and self-help support
groups through NGOs to be organized,
project proposals to be taken up for imparting
training to medical profession on the latest surgical techniques in
filariasis in selected medical institutions through ICMR in collaboration
with WHO and other bilateral agencies.
Pulse treatment with DEC as single dose annually in some
endemic countries has been found to possess:
the similar effectiveness as the 12 day
treatment as a public health measure,
It has lesser side effects thus enhancing
public compliance,
it involves decreased delivery costs,
it does not require complex management
infrastructure,
it can be integrated into the existing primary
health care system for delivery
single dose mass pulse treatment annually in
combination with other techniques already eliminated lymphatic filariasis
from Japan, Taiwan, South
Korea and Solomon Islands
and markedly reduced the transmission
in China.
It was proposed to observe a particular day every year for
National Filaria Day (NFD) which is to be observed in the 13 endemic
districts, covering a population of over 40 million. The extension of NFD to other endemic
places will be considered in a phased manner after evaluating the results
after the conclusion of the present pilot trials.
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