Virological investigation on the presence of CPV-2 in the Middle Black Sea Region of Turkey

Canine parvovirus (CPV) is a highly contagious agent prevalent worldwide, particularly in young dogs, and is associated with severe gastrointestinal symptoms. It is considered the leading cause of death due to haemorrhagic diarrhoea in puppies. As a result of antigenic and genetic changes in the virus, various variants such as CPV-2a, 2b, 2c, new 2a, and new 2b have emerged. This study aimed to investigate the presence of CPV-2 in the Black Sea region of Turkey and perform molecular characterisation. Samples were collected from dogs presented to the clinics of Samsun Ondokuz Mayıs University Faculty of Veterinary Medicine Animal Hospital with complaints of vomiting and diarrhoea. Blood, faeces, rectal swabs and tissue samples from 45 dogs suspected of CPV-2 infection were analysed using the real-time polymerase chain reaction method, which detected viral nucleic acid in 24 samples. Virus isolation was performed on the African green monkey kidney (VERO) cell line for eight positive samples. Whole-genome sequence analyses were conducted on six isolates using next-generation sequencing, classifying these isolates as CPV-2a variants. Among our isolates, three different amino acid changes were detected in the VP2 protein, the major capsid protein of CPV-2. The fact that two animals testing positive in this study had been previously vaccinated raises questions regarding vaccine effectiveness. In conclusion, our study provides insights into the current status of CPV-2 in the Black Sea region of Turkey and underscores the importance of conducting regular epidemiological studies and implementing an effective vaccination policy.