Psittacine Diseases Part One — Beak and Feather Disease

Psittacines, or parrots, are normally quite healthy and can live long lives. However, they are prey to certain serious diseases. In today’s blog, we’ll examine psittacine beak and feather disease (PBFD) caused by the circovirus. In our next blog, we’ll take a look at psittacosis, or parrot fever, a bacterial infection.


Parrot With PBFD, Bird Veterinarian
With Proper Care, Many Parrots Can Lead Long, Healthy Lives, Even With PBFD

PBFD affects parrots from the Old and New Worlds. The virus destroys feather follicles and attacks the parrot’s beak and claws. The virus causes distortion, cracking and peeling of the beak and claws, to the point where some infected parrots suffer beak fractures and can no longer eat. As the disease progresses, the feathers stop growing and fall out. The disease also attacks the bird’s thymus gland and its bursa of Fabricius, an organ that supports the parrot’s immune system. This makes the pet susceptible to secondary infections. The acute form of PBFD is often fatal and causes a number of symptoms, including:
• Sluggishness
• Vomiting
• Diarrhea
• Loss of Appetite

If the bird’s immune system is strong enough, the bird may survive with the chronic form of PBFD, in which damage to feathers, beak and claws has time to manifest. Feather loss may not appear until the parrot next molts after becoming infected.


The circovirus is a single-stranded DNA virus about 2,000 bases long. It is usually circular or 20-sided in shape, only 14 nanometers wide. There are two tests commonly used to diagnose the presence of circovirus: the polymerase chain reaction and the hemagglutination assay. The virus can be transmitted from parent to nestling, or from one flock member to another. Baby parrots have immature immune systems that make them susceptible to infection. The virus can spread through a number of vectors, including feather/skin debris, feces and craw secretions.

Prevention and Treatment
Fortunately, many adult parrots form a natural resistance to PBFD. However, younger parrots are more at risk. An infected adult can be a “Typhoid Polly,” transmitting the disease without actually contracting it. At this time, there is no specific treatment for PBFD.
Although the chronic form can’t be cured, your veterinarian can treat the symptoms caused by secondary infections. Once in a while, a parrot may recover from PBFD, but this is not usually the case. The decision on the whether to keep the parrot alive can depend on the severity of the symptoms. For example, if the bird only experiences feather loss without the other symptoms, it might be able to have a reasonably acceptable existence. However, if symptoms spread to beak and claws, you will have to have a serious talk with your veterinarian, who may recommend putting down the parrot.
The best course of action is prevention, and your veterinarian will be happy to educate you on ways to keep your parrot safe from the disease. The prudent approach is to quarantine a new parrot if you have other birds, and to have the new parrot tested for PBFD. If the parrot is a carrier of the disease but not a victim of it, you must always keep it isolated from other birds. Since parrots are gregarious creatures who love the company of friends and mates, this is a difficult decision for the owner. As always, your veterinarian is your best source of information and guidance.