Debashis Biswas

ABSTRACT

Anopheles stephensi (Liston) is the principal vector of malaria in the city of Kolkata. This mosquito is a night-biter. But in a study done in the mosquito research laboratory of Kolkata Municipal Corporation, 54% of the An. stephensi females studied were found to bite even at daytime. Registering such an unusual biting habit of An. stephensi apart, presence of its larvae in unclean water-holding containers/sites too was noticed in another study done during the winter season (November 2013 to February 2014). Surprisingly, water in some of the breeding sources of An. stephensi such as sumps, discarded water tanks and tyres, etc was grossly contaminated with organic matters, thereby suggesting that this vector mosquito, which normally breeds in fresh water containers, can breed in dirty water containers/sites too under ecological compulsion. Keywords: Anopheles stephensi, day-time, dirty water, ecological compulsion, Kolkata, malaria