The avian polyomavirus was recognized in the early 1981’s in Budgerigars and it was called the Budgerigar Fledgling Disease Virus. It is a small virus containing double-stranded DNA. Further investigation led to the conclusion that the Budgerigar Fledgling Disease Virus is a polyomavirus. Subsequently, it was found the virus can infect many different species of psittacine birds (parrots) and thus it is generally the convention to call it the avian polyomavirus (APV).

This pathogen was considered to be one of the most significant threats to captive birds worldwide (PBFD is now more prevalent). It is a highly infectious disease affecting almost all, if not all, parrots. Polyomavirus is severely dangerous for youth in the age 14-56 days with probable incubation period approximately 2 weeks and less. Young birds often die, while adult birds may develop some degree of immunity.

To the symptoms belong bloated abdomen, depression, little appetite, anorexia, low weight, vomiting, diarrhea, dehydration, abnormalities of feathers, bleeding under the skin, shortness of breath, ataxia, tremor, and paralysis. However, some of the infected birds can die without any symptoms. Adult individuals may die from secondary bacterial, viral, fungal or parasitic infection.



The disease is transferred from an infected individual to another with direct contact, inhalation of aerosol, ingestion of contaminated food, feeding the young, infection with feces, and feather dust, as well as contact with the infected environment (incubator and other).

Infected individuals which do not have usual symptoms of infection are often responsible for the spreading of the virus in aviaries. Adult individuals may be carriers.



Detection of Avian polyomavirus is performed by isolation of DNA from blood or feathers and following PCR or real-time PCR (qPCR).



The analysis is performed from the bloodstain, as well as for DNA-sexing (one bloodstain is enough for both analyzes).