Oral and transovarial transmission of La Crosse virus by Aedes atropalpus
Freier, J.E.; Beier, J.C.
American Journal of Tropical Medicine and Hygiene 33(4): 708-714
1984
ISSN/ISBN: 0002-9637 PMID: 6476218 Document Number: 225319
During a laboratory study in the USA, a recently colonized strain of Aedes atropalpus was shown to be equally susceptible to oral infection with La Crosse virus as the natural vector, A. triseriatus. La Crosse virus was shown to replicate and persist at high titres in orally infected females of A. atropalpus. These females also transmitted the virus efficiently to suckling mice by biting. Transovarial transmission of the virus was demonstrated by its recovery from larvae resulting from females infected either orally or by intrathoracic inoculation. The virus was recovered from larvae that developed from eggs produced both autogenously and anautogenously. Transovarial transmission of the virus to F1 adults was also demonstrated, and the filial infection rates were similar to that obtained with a strain of A. triseriatus used for comparison. Aedes atropalpus has become the dominant mosquito species in tyre yards in Indiana, USA, in the last few years. This study shows that a recently colonized strain is as susceptible to oral infection with La Crosse (LAC) virus as the natural vector Aedes triseriatus. The virus replicated and persisted in Ae. atropalpus and could be transmitted to suckling mice by bite; transovarial transmission was demonstrated, and virus could be recovered from progeny developing from eggs produced autogenously or anautogenously. The authors conclude that Ae. atropalpus should be investigated as "a possible new component in the natural cycle of LAC virus".Carolyn A. Brown.