[header] How to treat polyomavirus in caique parrots [title] Notice if the parrot has a loss of appetite and low energy. [step] One of the symptoms of polyomavirus is that the bird will stop eating and have low energy. It may appear depressed and lethargic. 
It may also have rapid weight loss due to lack of appetite. [substeps] The infected parrot may also vomit or regurgitate its food back up when it does eat.