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Bird fancier's lung is a type of hypersensitivity pneumonitis caused by bird droppings. The lungs become inflamed with granuloma formation.
Bird Fancier's Lung (BFL), also called bird-breeder's lung and pigeon-breeder's lung, is a subset of Hypersensitivity pneumonitis (HP). This disease is caused by the exposure to avian proteins present in the dry dust of the droppings and sometimes in the feathers of a variety of birds. It is mainly present in bird droppings, however. Birds such as pigeons, parakeets, parrots, turtle doves, turkeys and chickens have been implicated.
Risk of Infection
People who work with birds or own many birds are at risk. Bird hobbyists and pet store workers may also be at risk.
Symptoms
This disease is an inflammation of the air sacks in the lungs. If someone with BFL has been exposed to bird excreta they will see symptoms with in 46 hours. Symptoms include chills, fever, non-productive cough and chest discomfort. In the chronic form there is usually anorexia, weight loss, and progressive interstitial fibrosis which is the most disabling feature of the disease. This condition is occasionally fatal.
Treatment
BFL symptoms improve in the absence of the birds which caused the disease. An inhalation test and X-ray test are available to confirm whether someone has the disease or not. Steroids are used to treat a person with BFL. However, BFL may reoccur when in contact with birds.
References
Hargreave FE, Pepys J, Longbottom JL, Wraith DG. (1966). "Bird breeder's (fancier's) lung". Proc R Soc Med 59 (10): 1008. PMC 1901065. PMID 6005979.