Chapter 1: Introduction and significance in a shelter

Canine parvovirus (CPV) first made its unwelcome appearance in the late 1970’s and since then has continued to evolve, with CPV 2a, 2b and 2c gradually replacing earlier strains. As an un-enveloped, single stranded DNA virus, CPV is capable of persisting in the environment for months or even years. Unless vaccination is nearly ubiquitous in the surrounding community, periodic introduction into the shelter is inevitable. Because shedding can occur briefly in asymptomatic or pre-clinical animals, environmental contamination may go unrecognized. Disinfection, vaccination and housing practices must address this constant threat.

However, there is also some good news: although parvoviruses continue to evolve, they tend to be antigenically stable, and vaccination appears to confer reliable protection even against newer strains. In-house tests are reasonably reliable and readily available, thus recognition of CPV does not pose the diagnostic dilemma presented by some other conditions. The incubation period is well defined and relatively short (3-4 days but can be as long as 14), making quarantine of exposed animals a realistic possibility. Antibody titers can be used to assess risk in clinically healthy dogs, allowing further refinement of quarantine decisions. 

Although parvovirus will always pose a risk for most shelters, the rate of infection can be greatly reduced by appropriate vaccination; quick recognition; appropriate segregation of diseased/exposed animals; and careful cleaning and disinfection.