PBFD as explained by Many Avian Veternarians:
Psittacine Beak and Feather Disease - The virus causing this disease is a member of the Circoviridae. The molecular structure of the genome of the virus is roughly a 2,000 base, circular, single stranded DNA. PBFD virus has a strong resemblance to Porcine Circovirus as well as to a number of plant viruses such as the Banana Bungy virus.
The disease is thought to be specific for psittacines and all psittacine species should be considered susceptible. Parrots known to be particularly affected by PBFD include, but are not limited to, Cockatoos, Macaws African Grey Parrots, Ringneck parakeets, Eclectus Parrots, Lovebirds.
Causes fatal infections, primarily in young birds. Older birds may overcome the disease with few lasting affects. Some believe that these surviving birds become carriers able to shed the disease at a later date. Others believe that a percentage of birds are able to eradicate the disease from their system leaving them with a natural immunity that can be passed on to their offspring.
The virus that causes PBFD can also affect the liver, brain, and immune system causing diminished resistance to infections. Consequently premature early death usually occurs from these secondary bacterial, fungal, parasitic, or viral infections.
