Transovarial transmission of LaCrosse virus (California encephalitis group) in the mosquito, Aedes triseriatus.

LaCrosse virus (California encephalitis group) was recovered from F(1) eggs, larvae, and adults produced by experimentally infected Aedes triseriatus. The F(1) females transmitted the virus by bite to suckling mice and chipmunks. This, plus isolations of LaCrosse virus from larvae collected from their natural habitats in enzootic areas and from males and females reared from them, suggests that transovarial transmission is the overwintering mechanism for this arbovirus in northern United States.