On The Transmission of Bancroftial Filariasis on Ukara Island, Tanganyika. IV.—Host-preferences of Mosquitos and the Incrimination of <i>Anopheles gambiae</i> Giles and <i>A. funestus</i> Giles as Vectors of Bancroftial Filariasis

Abstract

Precipitin tests show that, on Ukara Island, Tanganyika, man and ox are the chief sources of blood to hut-resting mosquitos. Anopheles gambiae Giles and A. funestus Giles feed almost entirely on man. A. pharoensis Theo. feeds more on man than on ox. Culicines feed more on ox than on man. Hand-catches off man, cow and goat in a hut confirm the results of precipitin tests on hut-resting mosquitos. An account is given of the mosquito fauna of natural and artificial outdoor resting places and of the results obtained in precipitin tests on blood-fed mosquitos from outdoor resting places. Blood-fed mosquitos resting indoors and outdoors were examined for nucleated red corpuscles in blood-meals. A. gambiae and Gulex annulioris Theo. feed on domestic fowl. Experiments in the laboratory, to find the facility with which different species of mosquito will feed on small wild animals of the island, show that A. gambiae and certain Culicines feed on a wide variety of hosts. A. gambiae and A. funestus are incriminated as almost entirely responsible for the transmission of bancroftial filariasis on Ukara Island. A little transmission may take place by A. pharoensis .