Isolation of bluetongue virus serotype 2 from cattle in Florida: serotype of bluetongue virus hitherto unrecognized in the Western Hemisphere.

A serotype of bluetongue virus (BTV) hitherto unrecognized in the Western Hemisphere was isolated from cattle in the United States. Clinical disease was not seen in the cattle which were part of a sentinel herd system in Florida designed for studying the epizootiology of BTV. The isolation of serotype 2 was the first recovery of a different serotype of BTV in the United States since 1967. At least 21 serotypes of BTV have been reported worldwide; the 5 serotypes of BTV now recognized in the United States are 2, 10, 11, 13, and 17.