Development of a novel vaccine against canine parvovirus infection with a clinical isolate of the type 2b strain

PURPOSE: In spite of an extensive vaccination program, parvoviral infections still pose a major threat to the health of dogs. MATERIALS AND METHODS: We isolated a novel canine parvovirus (CPV) strain from a dog with enteritis. Nucleotide and amino acid sequence analysis of the isolate showed that it is a novel type 2b CPV with asparagine at the 426th position and valine at the 555th position in VP2. To develop a vaccine against CPV infection, we passaged the isolate 4 times in A72 cells. RESULTS: The attenuated isolate conferred complete protection against lethal homologous CPV infection in dogs such that they did not develop any clinical symptoms, and their antibody titers against CPV were significantly high at 7-11 days post infection. CONCLUSION: These results suggest that the virus isolate obtained after passaging can be developed as a novel vaccine against paroviral infection.