ORIGIN OF BLOOD MEALS IN INDOOR AND OUTDOOR RESTING MALARIA VECTORS IN WESTERN KENYA

Blood meals were obtained from indoor and outdoor resting malaria vect ors in three villages of western Kenya and tested by sandwich ELISA to determine host preferences and their human blood index (HBI). Anophel es gambiae s.s. collected indoors at Kisian village had a HBI of 0.97 while that of Anopheles arabiensis collected at Ahero was 0.23. Howeve r, the HBI of A. arabiensis varied depending on the availability of ou tdoor resting shelters. Most female A. arabiensis (98.9%) collected ou tdoors in granaries at Ahero had fed on cattle. Indoor-collected femal e Anopheles funestus had mainly fed on people (93.0%), but taken at le ast some of their blood (20.2%) from cattle. Although small numbers of A. arabiensis fed on sheep or goats and birds, none of the female A. gambiae s.s. and A. funestus tested had fed on these hosts. The absenc e of human-fed A. arabiensis in outdoor shelters indicated that exitin g after feeding, a behaviour pattern that mitigates indoor insecticida l spraying, is not prevalent in this species in western Kenya.