Disease emerged in Australia, United States, UK & Europe and spread rapidly on all 3
continents infecting dogs of all ages. Before this all canine sera were negative for
antibodies to CPV-2 but now most are positive. Feline vaccines have been thought of as a
possible source of CPV-2 but recent data suggests not and that parvoviruses from wild
carnivores could be the source. Variants have emerged (CPV-2a and CPV-2b) with only a few
changes in amino acids of the capsid protein gene. Only a few amino acids control the host
range. Faecal-oral transmission; resistant in environment.