Although the vast majority of infections have been identified in birds, CDC has received reports of WN virus infection in horses, cats, bats, chipmunks,skunks, squirrels, domestic rabbits, and raccoons. Following transmission by an infected mosquito, West Nile virus multiplies in the person's blood system and crosses the blood-brain barrier. Natural History of West Nile Fever, cont. Reservoir Hosts Isolated from numerous wild birds. Wetland and terrestrial species.
Birds are primary amplifier hosts.
Reservoir status not known. Migratory bird role in distribution and re-introduction of virus into northern latitudes. These crows will be banded and various data recorded. They nest at the very tops of trees in the thinnest of branches. A crow family group.