|Linthicum, Kenneth - Ken|
Submitted to: Journal of Medical Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/1/2007
Publication Date: 1/24/2008
Citation: Turell, M.J., Linthicum, K., Patrican, L.A., Davies, F.G., Kairo, A., Bailey, C.L. 2008. Vector Competence of Selected African Mosquito (Diptera: Culicidae) Species for Rift Valley Fever Virus. Journal of Medical Entomology. 45(1):102-108. Interpretive Summary: Rift Valley fever is an important viral disease of domestic animals and humans in Africa, and the potential for it to spread to other parts of the world have been documented. The virus has been isolated from numerous species of mosquitoes an transmission of the virus to domestic animals and humans is principally caused by mosquitoes. We evaluated 8 species of African mosquito species for their ability to transmit the virus in the laboratory, and we discovered that some species can transmit the virus better than other species.
Technical Abstract: Outbreaks of Rift Valley fever (RVF) in Egypt, Yemen, and Saudi Arabia have indicated the potential for this disease to spread from its enzootic areas in sub-Saharan Africa. Because little is known about the potential for most African mosquito species to transmit RVF virus (RVFV), we conducted studies to determine the vector competence of selected African species of mosquitoes for this virus. All eight species tested (Aedes palpalis (Newstead), Aedes mcintoshi Huang, Aedes circumluteolus (Theobald), Aedes calceatus Edwards, Aedes aegypti (L.), Culex antennatus (Becker), Culex pipiens (L.), and Culex quinquefasciatus Say, were susceptible to infection and all except Ae. calceatus, Ae. aegypti and Cx. quinquefasciatus transmitted RVFV by bite after oral exposure. Estimated transmission rates for mosquitoes that successfully transmitted RVFV by bite ranged from 5% for Ae. mcintoshi to 39% for Ae. palpalis for mosquitoes that fed on a hamster with a viremia >108 plaque-forming units of virus/ml. We did not recover RVFV from any of 3,138 progeny of infected female mosquitoes. RVFV is unusual among arboviruses in that it has been isolated in nature from a large number of species and that numerous mosquitoes and other arthropods are able to transmit this virus in the laboratory. The recent introduction and spread of West Nile virus into the Americas and the spread of RVFV to the Arabian Peninsula illustrates the potential for viruses, once enzootic in Africa, to spread to other parts of the world.