Bayesian Estimation of the True Prevalence of Caprine Arthritis Encephalitis in Hungarian Goat Herds.

Background: Caprine arthritis encephalitis (CAE) is a major viral disease of goats, caused by small ruminant lentivirus (SRLV), associated with chronic arthritis, mastitis, pneumonia, and encephalitis, leading to economic losses and reduced animal welfare. This study aimed to estimate the true prevalence of CAE in Hungarian goat herds, based on nationwide sampling and statistical modeling. Methods: Blood samples from 1218 goats in 53 herds were tested using ELISA, and true prevalence was estimated by Bayesian analysis. Results: The mean herd true prevalence (HTP) was 29.1% (95% CrI: 20.8-38.5%), while within the infected herds, the conditional within herd prevalence (CWHP) reached 58% ± 27.1%. Medium- and large-sized herds (>50 animals) showed the highest mean HTP (77.8% and 74.9%, respectively). No significant regional differences were observed, indicating that CAE is uniformly distributed across the country. Conclusions: Our findings place Hungary among moderately to highly affected European countries and highlight the need for a nationwide control strategy integrating routine serological surveillance, biosecurity improvements, farmer education, and long-term tools such as selective breeding.