The final lap towards elimination of Lymphatic Filariasis

Last month, the World Health Organisation (WHO) marked a breakthrough in the treatment and control of Lymphatic Filariasis (LF) by issuing guidelines on the new drug regimen.

Popularly known as the “Triple drug therapy,” (TDT), this treatment involving the drugs Ivermectin, Diethylcarbamazine and Albendazole is both preventive and therapeutic. Studies in Papua New Guinea, Cote d’Ivore and other countries have shown that TDT is more effective than the two drug therapy in permanently eliminating the micro filariae infection.

Lymphatic Filariasis is a “Neglected Tropical Disease” because it is traditionally underemphasised and prevalent in low-income populations of developing tropical regions of Africa, Asia, and the Americas. Commonly known as elephant’s foot, LF is caused by parasitic worms Wuchereriabancrofti or Brugiamalayi that are endemic in India and can lead to painful and disfiguring side-effects, such as severe swelling of the legs.

Even today, 31 million people in India are estimated to be infected with the disease and more than 23 million suffer from a disability associated with it, according to Indian Council of Medical Research (ICMR) estimates. India, which has 39 per cent of the world’s population at risk of Lymphatic Filariasis has adhered to the two drug therapy therapeutic approach of population based intervention through its Mass Drug Administration programme since 2004. While there has been progress, more remains to be done to eliminate it.

The new triple drug therapy holds out a promising opportunity to shorten the path to elimination in India and endemic countries around the world. However, the new drug therapy alone will not do. In India, there are daunting challenges to scaling up its administration especially across remote, rural and poor urban areas where the disease remains endemic. Challenges include tribal and migrant populations, inadequate diagnostics, non-compliance by beneficiaries over time.

India is committed to eliminate LF by 2020. The ICMR is coordinating efficacy trials on the triple drug therapy and will be coming out with its recommendations. Strong safety and efficacy data from other countries in Asia suggest that this approach may be promising for India. A timely scale-up of this regimen will need strong political commitment and inter-sectoral participation of stakeholders to bring more acceptance and participation from community for the new regimen.

Parallely, other factors, including individual hygiene need to be considered. Vector control or reduction of the breeding of mosquitoes that transmit LF from one person to another, is another. Residual spraying, sleeping under insecticidal nets and avoiding water logging prevent human-mosquito contact provide collateral benefits of protection from other vector-borne diseases such as dengue and malaria.

During my tenure as Chairman of the Technical Advisory Group for Lymphatic Filariasis (South-East Asian) region and former Director General of ICMR, I have witnessed tremendous progress in India and other countries in Asia towards the goal of elimination. India would be wise to take note of the global best-practices and the positive examples from our neighbours that have eliminated lymphatic filariasis. Bangladesh recently entered the post drug administration surveillance and Maldives and Sri Lanka are now undertaking surveillance post-validation of LF elimination.

To accelerate the last leg of LF elimination in India, we need to adopt new strategies, such as the use of triple drug therapy and focus on closing implementation gaps in our administration efforts. We look to the National Vector Borne Disease Control Program, Vector Control Research Centre and ICMR to make this a reality.

The writer is former Director General with the Indian Council of Medical Research (ICMR). Views expressed are personal.