During the summer of 1966, mosquitoes were collected in southeast Iowa for virus isolation. Although 19 species of mosquito were identified, Aedes trivittatus, Aedes vexans, Anopheles quadrimaculatus, Culex erraticus, Culex salinarius, and Culex tarsalis constituted 90% of the collection. Arboviruses were isolated from 17 of 201 pools of mosquitoes tested. These included a Turlock isolate from C. tarsalis, a Cache Valley virus from A. quadrimaculatus, 7 trivittatus isolates from 2 Aedes species, and 8 Flanders from 4 species of Culex. A known encephalitis-producing strain of the California encephalitis group was not isolated.
Present address: Johnson County Health Department, Olathe, Kansas 66061.