Between forest and farmland: serological evidence of exposure to Aujeszky’s disease virus, Coxiella burnetii and Chlamydia spp. in wild boars in Poland

Abstract Introduction This study assessed the seroprevalence of Aujeszky’s disease virus (ADV), Coxiella burnetii and Chlamydia spp. in wild boars in Poland. Material and Methods A total of 1,094 serum samples were tested. Antibodies against ADV were detected by ELISA, whereas Chlamydia spp. and C. burnetii were detected using the complement fixation test (CFT). For C. burnetii , phase I and phase II antibodies were assessed by CFT to differentiate between long-term and recent exposure. Multiple correspondence analysis was performed to evaluate associations between seropositivity, geographical origin and wild boar population density. Serological data were integrated with environmental factors, including African swine fever (ASF) occurrence, population density and forest cover, and were visualised spatially. Results Antibodies against ADV were detected in 455 samples (41.6%), those against Chlamydia spp. in 70 (6.4%) and antibodies against phase-I C. burnetii in 37 (3.4%) and phase-II in 30 (2.7%). Associations were observed between antibody presence, geographical location, wild boar density, pathogen co-occurrence and ASF-related environmental variables. Conclusion Wild boars in Poland show serological evidence of exposure to ADV, Chlamydia spp. and C. burnetii , supporting their role as sentinels at the wildlife–livestock interface.