Enrolling Breeding Sources of Anopheles stephensi (Liston) of Kolkata City, India, During Winter Season

Breeding sources of the prime malaria-bearing mosquito Anopheles stephensi of Kolkata City were enrolled during winter season (November 2013 February 2014). In all 10788 water containers/sites in 48 high-risk malarious wards of Kolkata Municipal Corporation were checked for An. stephensi larvae, of which 720 (7 %) were positive. Percentage positivity of water containers was much higher outdoors (11.4) than indoors (1.2). Sites with accumulated seepage water on rooftops of multistorey buildings were the most preferred breeding sources of An. stephensi (86.5 %; 135/156). The other important categories of its larval habitats included masonry tanks, water storage tanks and uncovered overhead water tanks. Detection of An. stephensi larvae in grossly contaminated water in sumps (29.4 %; 120/408) and some other containers/sites was quite startling. Findings of this study will help plan strategies for prevention of malaria in the city.