Prevalence of porcine circoviruses 2 and 3 in wild boar in Serbia

Porcine circovirus 2 (PCV2) and porcine circovirus 3 (PCV3) are prevalent pathogens that are economically important to the global swine industry. We investigated the prevalence of PCV2 and PCV3 in eastern Serbia by analyzing 166 wild boar samples with a real-time PCR assay. The cumulative prevalence of PCV2 and PCV3 was 72.7%, with true prevalence estimates of 59.2% for PCV2, 49.0% for PCV3, and 31.0% for coinfection. We found higher prevalence of PCV2 and PCV3 in the Južnobanatski district compared to previous reports, likely due to differences in detection methods and the inclusion of liver samples. Backyard farms, with free-ranging animals and natural breeding, dominate eastern Serbia, facilitating frequent interactions between wild and domestic pigs. The overlap between backyard and commercial farming practices, along with high wild boar densities and cross-border movements, likely facilitate viral transmission. These conditions, coupled with inadequate biosecurity measures, such as swill feeding and improper disposal of offal, amplify the risk for viral dissemination, with significant implications for spillover into domestic pig populations. Enhanced biosecurity and monitoring strategies are crucial to mitigate the risk of pathogen transmission between wild and domestic pig populations.