Full-length genomic and molecular characterization of Canine parvovirus in dogs from North of Brazil.

With the objective of characterizing Canine parvovirus (CPV) from some suspected fecal samples of dogs collected from the Veterinarian Hospital in Belém city, five positive samples were found by PCR assay and an update molecular characterization was provided of the CPV-2 circulation in Belém. Through sequencing of the complete DNA sequences (NS1, NS2, VP1, and VP2 genes), the CPV-2 strain was identified as CPV-2b (Asn426Asp) circulating in Belém. The CPV-2b strain with a different change at the position Tyr324Leu was detected in all samples assessed and thus reported for the first time for the scientific community. Phylogenetic analysis indicated that Belém CPV-2b and CPV-2a strains would be related to a cluster with samples after the 1990s, suggesting that CPV-2b in Belém originated from CPV-2a circulating in Brazil after the 1990s. Potential recombination events were analyzed using RDP4 and SplitsTree4; therefore, results suggest that CPV-2 sequences here described were not potentially recombination events. Continuous monitoring and molecular characterization of CPV-2 samples are needed not only to identify possible genetic and antigenic changes that may interfere with the effectiveness of vaccines but also to bring a better understanding of the mechanisms that drive the evolution of CPV-2 in Brazil.