ISOLATIONS OF POTOSI VIRUS FROM MOSQUITOS COLLECTED IN THE UNITED-STATES, 1989-94

Potosi (POT) virus, a recently characterized Bunyamwera serogroup viru s, was discovered when it was isolated from Aedes albopictus collected at a waste-tire site in Potosi, Washington County, Missouri, during 1 989. During the following year, POT virus was not isolated from 39,048 mosquitoes, including 17,519 Ae. albopictus, collected in Washington County. In 1991, mosquito collections from South Carolina, Ohio, and M ichigan yielded 8 strains of POT virus: 6 from Coquillettidia perturba ns and one each from Culex restuans and Psorophora columbiae. Addition al collections of Ae. albopictus from several states during 1990-93 fa iled to yield further isolates of POT virus. In 1994, POT virus was is olated from Ae. albopictus and Anopheles punctipennis in North Carolin a and from Ae. albopictus in Illinois. These represent the first virus isolations of any type from Ae. albopictus in those states. Thus far, POT virus has been isolated from 5 mosquito species in different gene ra in 6 states. The known geographic range of POT virus, based on viru s isolations, has been extended from Missouri to the upper Midwest and the Atlantic seaboard. Potential vector relationships and possible tr ansmission cycles of POT virus are discussed.