An Observation on the Loss of Microfilariae from the Mosquito Host during Its Infective Meal

Abstract

Anopheles quadrimaculatus has the habit of expelling one or more droplets of blood-tinged plasma from the anus during satiation feeding. In 31 mosquitoes used, the number of microfilariae found per anal droplet varied from 0 to 8, and the loss of parasites per mosquito varied from 0% to 17%. Of a total of 1599 microfilariae counted from the mosquitoes, 1487 parasites were found in the midguts and 112 (7%) were found in the dejecta. The loss of parasites by anal exudate is probably of no quantitative significance to the efficiency of this sp. of mosquito as host to the dog heartworm.