Time for a village-level strategy for the elimination of kala-azar (visceral leishmaniasis) in India: analysis of potential kala-azar outbreak situation in 2018.

Cases of kala-azar reported during 2013-2018 in Bihar, India were retrospectively analysed. Of 2187 villages reporting cases of kala-azar in 2018, 573 (26.2%) had reported no case in the previous five years but contributed to 20% of disease burden in 2018. On applying potential thresholds of kala-azar outbreaks, 805, 519 and 103 villages reported more than twice, thrice and five times their previous five-year annual average in 2018, respectively. Indoor residual spraying (IRS) in villages reporting any case of kala-azar in the past three years as per current guidelines could cover 72% of incident cases in 2018 vis-a-vis 80% if villages reporting cases in the past five years were considered. Therefore, IRS may be expanded to villages reporting cases in the past five years. Village case trends can be utilised to configure potential outbreak alarms (early warning and response system) on a pre-organised dashboard. A data-driven strategy for villages newly reporting cases and those in potential outbreak situations could prove effective in achieving and sustaining the elimination of kala-azar.