Present perspectives of malaria transmission in Boko area of Assam

A longitudinal study on malaria transmission was conducted from January 1984 to December 1988 in three villages in Boko PHC of Assam, where indoor residual DDT spray was withdrawn during the period of study. Anopheline fauna comprising of 19 species was identified and their seasonal density estimated. Anopheles philippinensis was the predominant species followed by An. minimus. The principal role of An. minimus in the transmission of malaria and predilection for indoor resting in this area was clearly evident. Though An. dirus and An. fluviatilis were found in low density, sporozoite infection was detected in them along with An. minimus. The high malaria incidence predominantly with Plasmodium falciparum was closely related to sporozoite infection in the vectors and their densities. The biting cycle of An. minimus was maximum in the first half of the night.