Though fortified rice, wheat, iodised salt, milk and oil are set to become a major part of the national malnutrition control plan soon, it seems the Government has not warmed up to the idea of providing fortified salt with the diethylcarbamazine (DEC) programme in States plagued by Lymphatic Filariasis (LF), a profoundly painful and disfiguring disease. This despite various studies asserting that a combination of fortified salt with the anti-filarial drug, DEC, could offer an intervention that avoids many of the barriers connected with tablet-based elimination programmes. The intervention has been successfully tried in several countries including India — which has 40 per cent of the world’s LF cases — and has been used operationally in China and Tanzania to eliminate the disease.
With just one year left to meet the 2021 target set by the Union Health Ministry for LF elimination, concerns are emerging regarding the feasibility of meeting the goal, using the current tablet-based Mass Drug Administration (MDA) strategy. At least 160 districts of the country are in the grip of LF, a neglected tropical disease that attacks the lymphatic system. It is caused by the transmission of filarial parasites that are transmitted to humans via mosquitoes. Currently, at least one million people in India are estimated to be infected by the disease and more than 23 million suffer from the disability associated with it, according to the Indian Council of Medical Research.
The LF elimination programme was kicked off in 2004, through the two-drug (DEC + Albendazole) MDA campaign, that requires a minimum of five years to interrupt transmission of the disease. But it has failed to deliver the desired results. In December 2018, India launched the World Health Organisation (WHO)-recommended triple drug therapy (TDT) comprising Ivermectin, DEC and Albendazole (IDA) in five States, viz, Nagpur in Maharashtra, Arwal in Bihar, Simdega in Jharkhand, Varanasi in Uttar Pradesh and Yadgiri in Karnataka. TDT is capable of accelerating the process of LF elimination in two-three years. However, the Government is facing a challenge as it plans to scale up the programme to 16 districts in Bihar, Gujarat, Karnataka, Maharashtra and UP to meet its goals. Though the WHO had provided the IDA for the pilot project, there are no international donations coming in for its extension programme and the Government will have to fund it to meet the deadline.
Rekha Shukla, Joint Secretary in the Union Health Ministry, says the demand is being calculated and tenders will be floated soon to invite firms to provide Ivermectin. “This might take around 12-14 months,” she admits. Given the long procedure of tendering and bidding, the effort to scale up the programme is likely to get delayed.
According to Shukla, the present LF elimination strategy has two pillars, comprising of MDA, morbidity management and disability prevention for patients. However, experts feel that it is high time that the low-cost and effective combination of DEC-fortified salt is considered. They pointed out that if more than one per cent of the population of an area tests positive for microfilaria, the parasite found in a person infected with LF, then it is considered an endemic zone and all efforts must be made to limit its spread. While DEC tablets often cause acute adverse reactions in people with high filarial loads and/or adult worms, DEC-fortified salt minimises this as it is given in lower doses.
It should also be possible to utilise a combination of both MDA with annual single-dose DEC plus albendazole and MDA using DEC-fortified salt. For example, DEC-fortified salt could be used in select areas while annual MDA of TDT could be carried out in areas where coverage is relatively easily achieved. The WHO suggests that MDA of 80 per cent of the eligible population in endemic areas is needed to stop transmission of and elimination of the disease. In India, where pill distribution is hampered by the effects of a transient population and illiteracy, DEC-fortified salt can be the solution. Neeraj Dhingra, head of the Health Ministry’s National Vector Borne Diseases Control Programme, too, said that DEC-fortified salt was under consideration but nothing had been finalised in view of some ethical and commercial issues pertaining to it. Nupur Roy, Additional Director, NVBDCP, pins hopes on combating LF with TDT itself. However, she also favoured DEC-fortified salt programme as an adjunct. “But then it is for the Government to take a call on it”, she added. However, Roy cautioned that salt fortification has its own challenges, similar to that faced in iodine fortification, and requires careful deliberation. “Greater emphasis needs to be placed in employing strategies tackling the source of the disease – preventing mosquitoes to human transmission,” says NK Ganguly, former DG, Indian Council for Medical Research and suggests residual spraying, sleeping under insecticidal nets and avoiding water logging as a preventive strategy.
(The writer is Special Correspondent, The Pioneer. This article was published with support from the India Science Media Fellowship 2019 by the Welcome Trust/ DBT India Alliance and Nature India )
