Transovarial Transmission of LaCrosse Virus (California Encephalitis Group) in the Mosquito, Aedes triseriatus

Abstract

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.

Mosquito-borne arboviruses in Norway: further isolations and detection of antibodies to California encephalitis viruses in human, sheep and wildlife sera

“…claviger is, however, a constant part of the fauna in the area where the virus-carrying mosquitoes were. Also, one of the isolates was from male mosquitoes, indicating the possibility of transovarial virus transmission (Watts et al 1973). …”

Rift Valley fever virus: strategies for maintenance, survival and vertical transmission in mosquitoes

“…This contrasts with the detection of LACV and CEV in the progeny of Aedes spp. in the first to fourth ovarian cycles [105,106], indicating VT efficiency is affected by the specificity of the vector-virus pairing.…”

Mosquito-Borne Arboviral Surveillance and the Prediction of Disease Outbreaks

“…In some cases, as for WNV in New York City, the virus survives in overwintering infected female mosquitoes (Nasci et al 2001). For other viral cycles, like La Crosse virus (family Bunyaviridae, genus Orthobunyavirus, LACV) in the upper Midwest of the USA, the virus survives through a process known as transovarial transmission in which the LACV survives through winter in cold-and drought-resistant eggs deposited by infected female mosquitoes during the previous autumn (Watts et al 1973). In other situations, viruses may be re-seeded into habitats by infected migrating birds.…”