The seroprevalence of canine parvovirus-2 in a selected sample of the canine population in ontario.

Canine sera, collected from dogs presented to the Ontario Veterinary College between 1976 and 1980, were assessed for canine parvovirus-2 antibody using a microtitre hemagglutination-inhibition test. Special emphasis was made on the period from September 1979 to October 1980 (2892 samples). No antibody was detected in samples collected in 1976 or 1977. The first positive sera were obtained in January 1978. By the end of 1978 antibodies to canine parvovirus-2 were widespread in Ontario dogs and in 1980, 683 of 2191 dogs (31.2%) had antibody. This was before widespread vaccination was being practised and indicates canine parvovirus-2 infection occurred frequently. Evaluation of clinical records of these dogs suggested that most infections had been subclinical.