Temporal patterns, co-infections, and risk factors of PaBV, BFDV, and APV in pet psittacine birds traded in Thailand

The legal trade of psittacine birds presents both economic opportunities and challenges, particularly in disease management. This study investigates the prevalence and co-infection dynamics of parrot bornavirus (PaBV), beak and feather disease virus (BFDV), and avian polyomavirus (APV) in psittacine birds traded in Thailand from 2020 to 2024. The study population consisted of clinically healthy birds. Molecular diagnostic testing identified PaBV and BFDV in 7.17 % and 7.94 % of samples, respectively, with significantly higher detection rates in birds from the Psittaculidae family (p < 0.001). APV was infrequently detected (0.57 %) and showed no significant variation across host families (p = 0.139). No significant associations were observed between viral prevalence and sex. Viral co-infections were identified in 0.52 % of birds, most commonly involving PaBV and BFDV. Among virus-positive individuals, the proportion of co-infections was highest in APV-positive birds (24.14 %), followed by PaBV (8.88 %) and BFDV (6.81 %). Temporal variation was observed in the monthly prevalence of PaBV and BFDV. However, further investigation is required to determine whether these fluctuations are associated with specific seasonal patterns. Our study emphasized the necessity of routine screening for PaBV, BFDV, and APV, which should be implemented, including clinically healthy birds, as clinically unaffected individuals may act as hidden reservoirs and contribute significantly to the ongoing disease burden within captive psittacine populations. Awareness of species-specific infection patterns and potential temporal variation can facilitate more targeted and effective disease monitoring in aviaries.