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Species of virus

Canine coronavirus (CCoV) is an enveloped, positive sense, single stranded RNA virus which is a member of the species Alphacoronavirus 1. It causes a highly contagious intestinal disease worldwide in dogs. The infecting virus enters its host cell by binding to the APN receptor. It was discovered in 1971 in Germany during an outbreak in sentry dogs.

The virus invades and replicates in the villi of the small intestine. Intestinal disease may be related to virus induced apoptosis (programmed cell death) of cells of the epithelial mucosa of the small intestine. Canine coronavirus was originally thought to cause serious gastrointestinal disease, but now most cases are considered to be very mild or without symptoms. A more serious complication of canine coronavirus occurs when the dog is also infected with canine parvovirus. Coronavirus infection of the intestinal villi makes the cells more susceptible to parvovirus infection. This causes a much more severe disease than either virus can separately. This may be related to the high mutation rate of RNA positive stranded viruses, of which canine coronavirus is one. The disease is highly contagious and is spread through the feces of infected dogs, who usually shed the virus for six to nine days, but sometimes for six months following infection. Known as canine respiratory coronavirus (CRCoV) and found to be similar to strain OC43 of bovine and human coronaviruses, it was first isolated in the United Kingdom in 2003 from lung samples of dogs and has since been found on the European mainland and in Japan. A serological study in 2006 has also shown antibodies to CRCoV to be present in dogs in Canada and the United States. However, a retrospective study in Saskatchewan found that CRCoV may have been present there as far back as 1996.