An occupational disease affecting the lungs of farm workers. Farmer’s lung is a type of allergic alveolitis, in which affected persons develop hypersensitivity (an excessive reaction of the immune system) to particular moulds or fungi that grow on straw, grain, or hay. The causative organisms thrive in damp, warm conditions, and outbreaks are most seen in areas of high rainfall.
Symptoms often develop, roughly six hours after the exposure to dust holding fungal spores. They include headache, fever, muscle attacks and shortness of breath. In acute attacks, the symptoms last for about a day. Recurring contact with spores can lead to a chronic form of the disease, causing permanent scarring of the lung tissues.
Diagnosis and treatment
Diagnosis of Farmer’s lung can involve a pulmonary function test; chest X-ray; and blood tests for a precise antibody to the fungus.
Corticosteroid drugs relieve the symptoms of the condition. Repeated exposure to the spores of the fungus should be avoided. Full recovery is probable if the disease is diagnosed before permanent lung damage has occurred.