Molecular Characterization and Phylogenetic Analysis of Canine Parvovirus Type 2 (CPV-2) in the Aizawl Region of Mizoram Reveals Circulation of CPV-2c Antigenic Variant: A Hospital based Study

Background: The objective of the present study was to confirm the presence of CPV-2 in dogs with acute gastroenteritis and to characterize the antigenic variants circulating in the Aizawl region of Mizoram, India. Methods: A hospital based epidemiological study was carried out from April, 2019 to January, 2020. Faecal samples were collected from the dogs with gastroenteritis and screened for CPV-2 infection by polymerase chain reaction (PCR). The distribution of positive cases according to various epidemiological factors was studied. Partial sequencing of VP2 gene was performed for the analysis of CPV-2 variants. Result: A total of 96 faecal samples were collected during the study period out of which 70 (72.91%) were found positive for CPV-2 infection. The distribution of positive cases was highest in young dogs of the age group between 3-6 months (47.14%), cross-bred (48.57%) and unvaccinated dogs (64.28%). The percentage of CPV-2 infection was relatively higher in male (54.28%) as compared to female dogs (45.71%). The analysis of nucleotide sequences from amplified products and phylogenetic analysis revealed presence of CPV-2a (1/5, 20.0%) and CPV-2c (4/5, 80.0%). Furthermore, sequence analysis of large number of samples is required to ensure the prevalent antigenic variant of CPV-2 linked to the infection.