Epidemiology of Visceral Leishmaniasis in India

Abstract

Kala-azar is a leading parasitic infection of great epidemic and mortality potential. More than 90% of Incident cases brought to notice of WHO in 2019 were mainly reported from 10 countries. Four endemic states in India namely Bihar, Jharkhand, Uttar Pradesh and Jharkhand have high disease burden of Kalazar. All 4 endemic states have to mandatorily notify cases to the National Vector Borne Disease Control Programme (NVBDCP) every month, even if there are zero cases. In recent years of Kala-azar cases, India have witnessed reduction of 97% largely due to the introduction of single-dose AmBisome –in India has been the game changer. There are three forms of leishmaniasis seen in India Kala-azar, they are Visceral Leishmaniasis, Post Kalazar Dermal Leishmaniasis (PKDL) and Cutaneous leishmaniasis. PKDL patients harbor the parasite and may be the source of new infection to the vector even 20 years later. Poverty enhances the risk for Kala-azar. Poor housing and domestic sanitary conditions are good breeding ground for sandfly which is the vector for Visceral Leishmaniasis, as well as resting sites and their ease of sandfly contact with humans. Kala-azar is a climate-sensitive disease as any change in temperature and humidity influences vector breeding.