Impact of IRS: Four-years of entomological surveillance of the Indian Visceral Leishmaniases elimination programme

Background In 2005, Bangladesh, India and Nepal agreed to eliminate visceral leishmaniasis (VL) as a public health problem. The approach this was through improved case detection treatment, controlling transmission by the sand fly vector Phlebotomus argentipes , with indoor residual spraying (IRS) of insecticide. Initially, applied DDT stirrup pumps for IRS, however, did not reduce transmission. After 2015 onwards, pyrethroid alpha-cypermethrin compression pumps, entomological surveillance initiated in 2016. Methods Eight sentinel sites were established Indian states Bihar, Jharkhand West Bengal. IRS coverage monitored household survey, quality insecticide application measured HPLC, presence abundance VL CDC light traps, resistance WHO diagnostic assays incidence determined from register KAMIS. Results Complete treatment houses increased across all 57% 2016 70% 2019, rising >80% if partial house is included (except Bengal). has compared previous studies, average doses on filters papers ranged 1.52 times target dose 25mg/m 2 2019 1.67 2018. Resistance continued increase, but resistant carbamates, organophosphates or pyrethroids. annual seasonal P . declined between an overall infection rate 0.03%. This associated decline blocks represented 1.16 per 10,000 population 0.51 2019. Conclusion Through effective management reducing reservoirs human combined keeping infectivity low reduced combination control now brought within reach elimination targets.