Isolation of Bluetongue Virus from a Calf and Antibody Survey among Cattle in Okinaw

Abstract

During the period from May to December in 1985-1990, sentinel calves were located in several parts of Okinawa Prefecture for virus isolation and serological survey of arboviruses. A virus designated ON-89-1 was isolated in June 1989 from blood cells of a healthy calf located in the Central Okinawa Island using HmLu-1 cell cultures. The isolate was identified as a member of the Orbivirus by morphology and physicochemical properties, cross-reacting with bluetongue virus (BTV) by immunodiffusion and being neutralized by antiserum to BTV serotype 21. A serologic survey revealed seroconversion in the summer of each year and wide-spread dissemination among cattle throughout the Prefecture.