Current status of canine parvovirus infection in dogs in India and its pathogenesis

Canine parvoviral infection is caused by canine parvovirus type 2 (CPV-2) belonging to genus canine parvovirus and family Parvoviridae, which is one of the most dreadful diseases affecting the canine population. It causes severe haemorrhagic gastroenteritis in adult dogs and myocarditis in puppies with high morbidity and mortality rate. The CPV-2 has been globally replaced by the newer antigenic variant viz., CPV-2a and CPV-2b. In Ihdia, the disease has got an emerging status, as it has been reported in different breeds of dogs and from various parts of the country. Although both live attenuated and inactivated vaccines are available for use in dogs, vaccination against parvovirus does not provide foolproof coverage against the disease and infection. Further, the vaccine manufacturers do not disclose the strain/mutant used in preparing the vaccine and available in the market as multivalent vaccine along with other viral as well as bacterial diseases. The improper protection against CPV may be due to the mismatching of the vaccine strain and the outbreak strain of CPV. Moreover, in India there exists an alarming population of canines which harbor and shed the virus, thereby acting as potential source of infection to other susceptible populations. The diagnosis jis often carried out by HA and isolation in the MDCK and CRFK cell lines. They suffer from less sensitivity and there is a requirement of porcine RBC in the former and cell culture facility in the later. To overcome these difficulties, recently PCR and Real time PCR which have been found to be highly sensitive, specific and reliable and employed to diagnose the disease from the suitable samples. The results of PCR has been again substantiated by nested PCR and RE mapping. The prompt and accurate result obtained from PCR makes it extremely useful for effective and efficient management of the disease.