Animals Involved
Chipmunks, squirrels are major amplifying hosts; rabbits, foxes, and other mammals can be infected
Known Distributions
North America
Probable Means of Spreading
Mosquito bites
Clinical Manifestations in People
Many cases mild and flulike; meningitis or encephalitis with seizures, paralysis, and focal neurologic signs possible; most cases in children; estimated case fatality rate <1% in cases with encephalitis