Epidemiology and Molecular Characterization of Feline Calicivirus in Beijing, China

Feline calicivirus (FCV) is an infectious pathogen in cats that mainly causes upper respiratory tract disease. Enhancing our understanding of the epidemiological characteristics of FCV can contribute to better strategies against FCV infection. To investigate the prevalence of FCV in Beijing, explore the risk factors associated with FCV infection and elucidate its genetic evolutionary characteristics. Cats (n = 402) from the China Agricultural University Veterinary Teaching Hospital (CAUVTH) were investigated from June to December in 2023. The rate of FCV-positive cats in the sample examined was 31.3%. Risk factors significantly associated with FCV infection were age, vaccination status and residential density by Logistic regression analysis. Phylogenetic analysis of completed genomes revealed a radial phylogeny, with no obvious geographical clustering. Amino acid analysis at different sites of E region of the major capsid protein revealed variable neutralizing antibody epitopes, while feline junctional adhesion molecule-A (fJAM-A) binding sites remained conserved. Additionally, the first FCV recombinant isolate was detected in Beijing, originating from two 2019 isolates collected in the city. This study elucidates the molecular epidemiology and genetic diversity of FCV in Beijing, which provides valuable insights for the development of effective measures for FCV prevention and control.