Fig. 5.

Enzootic and epizootic/epidemic transmission cycles of Western equine encephalitis virus (WEEV). WEEV is maintained in an enzootic cycle between passerine birds as reservoirs and its specific mosquito vector, C. tarsalis. Domestic and wild birds are considered important reservoir and epizootic amplifying hosts. It has also been suggested that lagomorphs and rodents can serve as amplification hosts when they are infected with WEEV by Aedes mosquitos.