Isolation of Rift Valley fever virus from mosquitoes (Diptera: Culicidae) collected during an outbreak in domestic animals in Kenya.

During an outbreak of Rift Valley fever (RVF) in livestock near Lake Naivasha, Rift Valley Province, Kenya, 61,347 mosquitoes (1,287 pools) collected in CO2-baited light traps yielded seven viral isolates. Five isolates of RVF virus were recovered from 18,831 Culex zombaensis Theobald and one from 14,439 Mansonia africana (Theobald). One isolate of a Bunyamwera group virus was recovered from 1,175 Aedes quasiunivittatus (Theobald).