Press Release

ERADICATING FILARIASIS

IT MAY NOT be a killer like malaria, but lymphatic filariasis is not a disease to be taken lightly. Better known as elephantiasis, it can lead to grotesquely enlarged arms, legs, genitalia, and breasts. Over 128 million people are estimated to be suffering from the disease worldwide, about 40 per cent of them in India. The disease is caused by tiny, thread-like worms whose larvae are transmitted from person to person by mosquitoes. The larvae make their way to the lymphatic system, a network of nodes and vessels that returns fluids from the tissues to the bloodstream and is a key part of the body's immune system. There the larvae develop into male and female worms that breed to produce millions of immature larvae, which then circulate in the bloodstream. After a mosquito ingests the blood of an infected person, these immature larvae develop further inside the mosquito and reach the infective stage where they can set off another cycle of infection. The development of the disease is not still fully understood as it appears to be generally acquired in childhood and manifests itself only many years later. Some infected people may show no outward signs of the disease.

Countries where this dreadful disease is common have embarked on a strategy that aims to eradicate it. The strategy is to administer drugs that can kill the worms and the larvae they produce so that the cycle of infection is broken. A single dose of the drug is administered for at least five years to the entire population of an endemic area. This strategy was ratified in 1997 by the World Health Assembly, the supreme governing body of the World Health Organisation, and the Global Programme for the Elimination of Lymphatic Filariasis was established in 2000 to execute it. Mass drug administration using diethylcarbamazine citrate (DEC) was tried out in Cuddalore district in Tamil Nadu in 1996. Its success led to the programme being, expanded and last year 31 districts in seven States were covered. This year, however, the Government plans a major expansion, with mass drug administration being carried out in 250 districts in 20 States where the disease is endemic.

But unless more is done to address public concerns and secure widespread cooperation, such ~ an expansion could be counterproductive. The safety and tolerability of the drug combinations have been confirmed by their increasingly large scale use, points out a paper published recently by a WHO expert; an estimated 60 million people in 34 countries were administered the medicines in 2002. However, experts say that adverse reactions, which are not life threatening and are easily treated, are seen in a small proportion of people as the drugs kill the worms and their larvae. The most important thing is to prevent such occurrences from setting off panic reactions. That is just what seems to have happened in early June when the mass administration of DEC was carried out in the endemic districts of Karnataka. Newspaper reports spoke of several people taking ill, and of five deaths. Medical investigators have since concluded that deaths were the result of other ailments, and not related to the taking of DEC. The episode shows the importance of educating the public and doctors in the area where mass drug administration will be carried out, and enlisting their support. Moreover, the Government must be in a position to give credible assurances to people that medical help would be readily available should they experience any adverse reaction after taking the drug. Without sustained and widespread public support, the anti-filariasis programme can fail.