A Meta-Analysis of Global Prevalence of Psittacine Beak and Feather Disease Virus Infection and Associated Risk Factors

Beak and feather disease virus is a member of the family <i>Circoviridae</i>, and among birds, parrots are susceptible hosts. This study reported the global molecular prevalence and risk factors of BFDV infection in parrot species. Relevant studies were identified from PubMed, Scopus, Web of Science, China National Knowledge Infrastructure (CNKI), and WanFang databases. We retrieved 30 studies encompassing 16,901 parrots from 30 species across six continents and 34 countries, all published between 2003 and 2024. The results showed that the global molecular prevalence of BFDV, based on eligible areas, was 16.30% (95% CI, 11.40-22.00%) using a random-effects model. Subgroup analysis showed that there were significant differences among genera, with <i>Agapornis</i> having the highest prevalence of 26.60% (95% CI, 9.80-46.50%). There were significant differences in prevalence rates among the four sampling methods (<i>p</i> < 0.01) (blood, cloacal swabs, feather, and fecal). Blood samples exhibited the lowest prevalence at 11.2% (95% CI: 4.4-20.7%), suggesting that BFDV prevalence may be underestimated if only blood tests are used. In regions with distinct seasonal variation, the prevalence of BFDV (3.80%, 95% CI: 0.10-11.10%) was notably lower in summer, but higher in spring and autumn. Age subgroup prevalence varied significantly, with young birds having the highest prevalence at 22.5% (95% CI, 8.8-39.6%). No significant differences in the prevalence of BFDV were observed based on sex or sampling time. This study indicated that the global molecular prevalence of BFDV infection has increased in recent years, and that species, season, sampling methods and age are the main risk factors. By monitoring BFDV prevalence, identifying high-risk species, and elucidating key risk factors, we can develop targeted management strategies to mitigate viral transmission.