Polyoma Virus

Polyomavirus is a deadly infection that affects many of the bird’s body parts and organs simultaneously. This infection affects caged birds, especially those from the parrot family. Young birds from new-born to juveniles (14-56 days), are the birds most at risk and is usually fatal. Though not proven, adult birds are thought to form some immunity to polyomavirus.

Symptoms and Types

From the time the bird contracts the infection, it takes about 10-14 days for the it to display symptoms. However, a bird may or may not show any sign of the polyomavirus infection. If the symptoms are displayed in your bird, its death may be imminent — usually within one or two days. Since the infection lowers the immunity of the bird, it can be susceptible to other viruses, bacteria, fungi and parasites, which can lead to secondary infection and death.
Birds with polyomavirus infection may display symptoms, including:

– A swollen (distended) abdomen
– Loss of appetite
– Regurgitation
– Vomiting
– Diarrhea
– Dehydration
– Weight loss
– Depression
– Feather abnormalities
– Excessive urination
– Difficulty breathing
– Bleeding (hemorrhages) below the skin
– Listlessness
– Tremors
– Paralysis


The polyomavirus is usually contracted through direct contact with other infected birds. It is also contracted from infected feces, dander, air, nest boxes, incubators, feather dust or from an infected parent passing it to chick.

How do birds become infected?

Direct exposure of non-vaccinated birds to a bird infected with polyomavirus or a non-symptomatic carrier is the most common route for transmission. Humans that have handled a sick bird or carrier bird, used feeding utensils from sick baby birds, or do not thoroughly disinfect food and water bowls can carry the virus on their person and infect other birds. Feather dander and bodily fluids from infected birds are also a frequent source for transmission to other birds.

There is no known treatment for the polyomavirus disease.

Following strict hygiene methods, such as disinfecting nest boxes, cages, incubators or utensils, can help ensure your bird does not get infected with the polyomavirus. The virus, however, is resistant to most disinfectants; use oxidizers like chlorine beach instead. Aviaries and pet stores should also regularly screen for the virus. And new birds should be quarantined to ensure they do not carry the disease.

Vaccination is available, but its effectiveness has still not be proven. The vaccine is given as a double dose to young birds. The first dose is given at four weeks of age, and second dose is given between six to eight weeks of age.