Clinico-pathological and Molecular Investigations with Evidences of Circulation of a Highly Virulent Canine Parvovirus (CPV) Serotype in Egypt

This study was designed for better understanding of the variability of clinical forms of canine parvovirus (CPV) infection as well as detection and characterization of the current genotypes of CPV in Egypt during 2022- 2023. A total of 78 dogs suffering from fever, vomiting, diarrhea and dehydration suggesting CPV infection at Al-Fayoum, Cairo and Beni Suef governorates, Egypt were employed. Fecal swabs were collected from dogs under different risk variables and subjected to ICA using a rapid test antigen kit as well as partial amplification of VP2 gene using PCR, sequencing and phylogenetic analysis. Out of 78 fecal samples, 68 were positive (87.18 %) by ICA. ICA confirmed the presence of the virus in the feces in the early stage of the disease just after manifestation of clinical symptoms. Different risk factors associated with CPN infection including, age, sex, breed, vaccination status and seasons were investigated. Puppies of young age and exotic breeds were more predisposed to CPV infection. Infection of vaccinated dogs confirmed the failure of vaccination that may be due to using a vaccine that does not contain the virus circulating in the areas of study. Variable clinical forms were recorded and discussed on pathological and hematological basis. Sequencing, BLAST analysis of two purified PCR products obtained from two dogs revealed CPV-2c. The generated sequences were registered at the GenBank database under the accession numbers: PQ031242.1 and PQ031243.1. Phylogenetic analysis proved that they are closely related and share 99.9:100 % nucleotide and amino acid identities with other Egyptian strains available in the database. The current study endorses further studies to assess the efficiency of the vaccines employed in Egypt in protection against CPV infection.