Molecular Characterization of Canine Distemper Virus (CDV) in Suspected Dogs Referred to Civil Veterinary Hospital, Peshawar, Khyber Pakhtunkhwa, Pakistan

Canine distemper (CD) is a highly contagious viral disease caused by Canine Distemper Virus (CDV) and remains a major health concern in dogs worldwide. This study investigated the molecular prevalence and associated risk factors of CDV infection in clinically suspected dogs presented to the Civil Veterinary Hospital, Peshawar, Khyber Pakhtunkhwa, Pakistan. Clinically suspected dogs were identified based on signs including anorexia, pyrexia, vomiting, diarrhea, coughing, and respiratory distress. Blood samples were collected from owned dogs presented for clinical examination during the study period. Because sampling was restricted to a single veterinary hospital and only clinically suspected animals were included, the findings may be influenced by selection bias and should not be generalized to the broader dog population. A total of 392 blood samples were analyzed by RT-PCR targeting the nucleocapsid (N) gene of CDV, with appropriate positive and negative controls included in each reaction. Overall, 47.95% of samples tested positive. Among positive dogs, anorexia was the most common clinical sign (67%), while vomiting showed the strongest statistical association with CDV positivity (p = 0.000). Statistical analysis revealed significant associations between CDV infection and breed, season, and vaccination status (p < 0.05), whereas age and sex were not significantly associated. Certain breeds, including Dachshunds, local “Enty,” “Kochani,” and Pointer dogs, showed 100% positivity; however, these findings should be interpreted cautiously given the limited breed-specific sample sizes. Summer had the highest seasonal prevalence (70.40%). Vaccinated dogs also tested positive (61.9%), although this should not be interpreted as vaccine failure, as detailed vaccination histories were unavailable. Phylogenetic analysis of partial N gene sequences showed close clustering with the America-1 vaccine strain, with nucleotide identities ranging from 94.36% to 98.43%, highlighting the need for continued molecular surveillance and vaccine efficacy studies.