Genetic characterization and evolutionary analysis of canine parvovirus in Tangshan, China.

Canine parvovirus (CPV) is a major enteric virus of carnivores worldwide that poses a considerable threat to dogs. In this study, we investigated the genetic variation of CPV in Tangshan, China, and the relationships between CPV disease and the vaccination status, age, and gender of dogs. Seventy-seven fecal samples from dogs in Tangshan that tested positive for CPV were obtained for analysis. Twenty-two full-length VP2 gene sequences were successfully amplified. The 22 strains included 17 CPV-2c variants, four new CPV-2a variants, and one new CPV-2b variant. Phylogenetic analysis showed that all of the CPV-2c strains clustered together and were closely related to CPV-2c strains from Asia but distantly related to CPV-2c strains from Europe. Further amino acid sequence analysis showed that, relative to CPV-2c strains from Europe, most of the CPV-2c stains in this study had A5G, F267Y, Y324I, and Q370R mutations. These findings provide a more comprehensive understanding of the variants of CPV circulating in China.