Molecular Characterization of Canine Parvo Virus Variant-2 in Cats in Chennai by Amplification-Refractory Mutation System Polymerase Chain Reaction

Abstract

Background: Feline panleukopenia virus and canine parvovirus infections are highly contagious and serious enteric diseases of cats and dogs with high fatality rate. Canine parvo viral enteritis (CPV) is caused by CPV-2 antigenic variants (CPV-2a, 2b, 2c) is frequently reported in dogs worldwide leading to morbidity and mortality Infection in cats by canine parvo virus variants causes clinical signs similar to feline panleukopenia virus. CPV-2 variants have recently acquired the feline host rage, allowing it to infect both cats and dogs. Feline Panleukopenia virus is not the only parvovirus species affecting cats, in addition to Mink enteritis virus, the new variants of canine parvovirus, CPV-2a, 2b and 2c have also penetrated the feline host-range, and able to infect and replicate in cats, causing diseases indistinguishable from feline panleukopenia. The present study was taken to identify the canine parvovirus variants among domestic cats in Chennai and its role in transmission of CPV-2 between dogs through Amplification refractory mutation system. These findings suggest that species jump of CPV from dog to cats as well as CPV had presumably started a new process of readapting in feline hosts and confirmed the importance of viral host switching as a mechanism for the emergence of new viruses. Methods: In this study around 166 cat faecal swabs were collected during 2020-2022 in and around Chennai which were brought with the clinical signs of vomition and diarrhoea. Collected faecal samples were subjected to DNA extraction and Amplification Refractory Mutation System Polymerase Chain Reaction and 50 cat samples showed positivity towards canine parvovirus infection. Result: Of 166 faecal samples, 50 samples showed positive for the CPV-2a variant. By ARMS-PCR In this case, the 50 samples responding to outer forward and inner reverse primers and yielding a 492 bp amplicons in addition to the 631 bp common outer product as CPV-2a/2. This study suggested that CPV infection in cat showed that CPV has started a new process of readaptation in the feline host and confirming the importance of viral host switching mechanism as a mechanism for the emergence of new viruses. The introduction of CPV into the feline population raises concern about the efficacy of FPV-based vaccines in preventing CPV infection and point out the necessity for intensifying surveillance of parvovirus infection in cats.