Mosquito age as a factor influencing the transmission of Wuchereria bancrofti.

Two mosquito species; Culex pipiens and Aedes caspius of different ages were experimentally infected with moderate microfilarial densities of Wuchereria bancrofti and examined for their vector potential to transmit this parasite. Tested age groups of Cx. pipiens supported the development of the infective stage of the parasite (L3) but those of Ae. caspius arrested its development especially aged mosquitoes. For Cx. pipiens, infection rates and the mean number of microfilaria (mf) were found decreased with insect age groups while their survival was not affected. Also, proportion of mosquitoes harbouring L3 of the parasite was quite similar for the examined age groups, however; the 4 days-old group was the highest. On the other hand, Ae. caspius capability to respond against W. bancrofti was decreased in older mosquitoes. The observed results may indicate certain influence of mosquito aging on the development of W. bancrofti which differ according to mosquito species.