Hemagglutination-inhibition, complement-fixation, and neutralization tests in mice were used to detect antibody to 11 arboviruses in 1.389 samples of bovine serum, collected in Queensland, Australia. The neutralizing activity of bovine antibody was low. Evidence is presented that indicates that the serologic response to some arboviruses is short-lived. Group A: Antibody to Ross River virus occurred in 98 serum samples; it was widespread in Queensland but was more prevalent in the southeast. Antibody to Getah virus occurred in 32 serum samples, also widespread but more prevalent in northern areas. Antibody to Sindbis virus occurred in only 13 serum samples, mostly from southeast Queensland. Group B: Thirty-two serum samples had antibody to Murray Valley encephalitis virus, and 29 had antibody to Kunjin virus. Most of these were from North Queensland. One cow had high-titer antibody to Kokobera. There was equivocal evidence for antibody to Stratford, Edge Hill, and MRM 3929 viruses. Koongol group: There was evidence of a low incidence of infection.
Present address: Department of Pathology, Tennis Court Road, University of Cambridge, Cambridge, England.