Also known as Psittacine Circovirus Disease, PBFD, which is incurable, has been identified in over 60 species of wild and captive parrots. It has been much in the news lately, and the questions I’ve received indicate that some of the coverage has been confusing to bird owners. Today I’d like to summarize what we know, and what remains to be done in the battle against PBFD.
PBFD Natural History
The virus that causes PBFD was first described in 1987, when it was discovered in a captive group Orange-Bellied Parrots, a highly endangered species. Further study revealed that the virus occurred naturally in Australia, and likely was endemic there (found nowhere else). The disease is now established worldwide, apparently having been spread by the legal and illegal trade in parrots.
The PBFD virus is an extremely hardy organism, and likely survives for many years in nest hollows and roosting/feeding areas. To date, only one disinfectant, Virkon S, has proven able to kill it. The virus has been found in feather dust, feces and the crop lining of infected birds. Transmission seems to occur in several ways – direct contact with sick birds, inhalation of the virus from dust and feces and via food passed to chicks by parents.
PBFB may incubate within a parrot for 3 weeks to 12 months, during which time symptoms will not be visible. Birds incubating the virus will, however, shed it in the feces and feather dust, and thus infect others. In rare cases, adult parrots may survive PBFD. Unfortunately, they continue to shed the virus even after full recovery.
The Various Forms of PBFD
Three forms on PBFD have been identified. Peracute PBFD affects newly-hatched chicks and is usually fatal within 2-3 weeks. As feather abnormalities are not visible, this form is usually diagnosed only upon necropsy.
Acute PBFD is seen among nestlings that are developing their first feathers, and usually causes death within weeks. Infected birds become lethargic, and may vomit and exhibit abnormal feather growth (please see below).
Adult parrots afflicted with Chronic PBFD exhibit feather abnormalities such as the loss of powder down, curled feathers, retained sheaths and color changes. The beak, especially in cockatoos, may flake and crack, and nails may curl as they grow. Diarrhea, lethargy and vomiting may are often present.
PBFD is most accurately diagnosed via a blood test.
Immune System Effects
In addition to causing feather, nail and beak destruction, PBFD depresses the immune system. Death often results from secondary infections (i.e. septicemia and pneumonia) caused by opportunistic bacteria. Cracks in the beak, and skin wounds caused by abnormal feather growth, likely worsen the situation by providing an easy route for bacterial infection.
Managing PBFD in the Wild
PBFD is considered to be a serious threat to the survival of several rare Australian species, including the Swift, Orange-Bellied and Norfolk Island Green Parrots. Australia’s Environmental Protection and Biodiversity Act provides for a PBFD management program (please see article below).
Research into the development of a vaccine is ongoing, but success is not expected in the near future.
Managing PBFD in Captivity
While there is as yet no cure for PBFD, there are some steps that can be taken to increase the quality of life for infected pets. As is true for all creatures, a proper environment and diet will strengthen the immune system and possibly reduce the severity of the disease or its symptoms. Exposure to sunlight or artificial UVB, a natural photo-period (day/night cycle) and an appropriate diet have been found useful (please see article below).
If you maintain a parrot collection, newly-received individuals should be kept in isolation until they have been checked for PBFD. Due to the severity of the symptoms, one may need to consider euthanasia as the disease progresses.
Arizona Exotic Animal Hospital Information, with tips on caring for infected Parrots
PFBD Infected Cockatoo image referenced from wikipedia and originally posted by S B and Snowmanradio