Psittacine Beak and Feather Disease: Global Spread, International Trade, and Conservation Challenges

Psittacine Beak and Feather Disease (PBFD) is a highly contagious viral condition caused by Circovirus parrot-commonly known as Beak and Feather Disease Virus (BFDV)-a small, single-stranded DNA virus of the family Circoviridae. The disease primarily affects parrots (order Psittaciformes) and is characterized by progressive feather dystrophy, beak deformities, immunosuppression, and high mortality rates, particularly in juvenile birds. Although PBFD was initially documented in Australian psittacines, the virus has now attained global distribution, facilitated predominantly by the international trade in live parrots, both legal and illegal. This review provides a comprehensive synthesis of current knowledge on the virology, clinical presentation, molecular epidemiology, and phylogeographic spread of BFDV. Particular attention is given to the role of parrot trade in shaping transmission dynamics and genetic diversification. The review further evaluates existing biosecurity policies, diagnostic challenges, and disease management strategies within both captive and wild avian contexts. Given PBFD's dual status as a veterinary concern and a growing conservation threat, strengthening international surveillance, regulating wildlife trade, and integrating molecular diagnostics into routine screening are critical priorities. Effective containment of BFDV requires a multidisciplinary approach involving veterinarians, aviculturists, conservation biologists, and policymakers to safeguard the health and genetic viability of endangered psittacine species globally.