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What is Farmer's Lung?

Felicia Dye
Felicia Dye

Farmer's lung, formally known as extrinsic allergic alveolitis, is a type of allergic pneumonia. The disease is caused by inhaling dust that is carrying certain types of mold or bacteria. This disease is mostly found among farmers, but it may also inflict those who have no connection to the agricultural industry.

Analyzing the formal name of this disease can provide a bit of insight on the disease. Extrinsic denotes something from outside. Alveolitis refers to inflammation of the alveoli. The alveoli are small sac-like structures on the lungs that allow carbon dioxide to exit the bloodstream and oxygen to enter it.

A human respiratory system.
A human respiratory system.

Farmer's lung is caused when a person has an allergic reaction to particles he inhales. That allergic reaction causes swelling of alveoli. As a result, the person is likely to experience breathing difficulty. The more severe the case, the more severe the associated symptoms can be. Symptoms include chronic coughing, tightness of the chest, and feelings of general illness.

Exposure to contaminated hay can cause farmer's lung.
Exposure to contaminated hay can cause farmer's lung.

For agricultural workers, the disease is commonly caused by exposure to contaminated hay. It is highly unlikely a person will develop farmer’s lung from a single exposure or from brief exposures. The disease generally develops as a result of excessive and prolonged exposure.

Although farmer's lung is noted to be most common among agricultural workers, it is not restricted to such individuals. Anyone who is exposed to intense or repeated inhalation of contaminated dust can be inflicted with the disease. The organisms that cause farmer's lung can be found in ventilation systems. This explains how an office worker, for example, could be found with the disease.

It has been noted that people are most likely to contract farmer's lung in cold, damp conditions. Those with the disease may find it worsens in winter. There are two likely reasons for this. One, the allergens that cause the condition tend to like damp environments. Two, there is usually poorer ventilation during cold periods.

The disease can often be treated by changing environments. If a person can avoid inhaling further allergens, there is a possibility of recovery. When this is not possible, however, a person with farmer's lung faces serious risks. For example, it has been noted that there is an increased risk of mortality if a person suffers with symptoms of the disease for more than a year before being diagnosed. In more severe cases, medication may be necessary to facilitate breathing and alleviate other symptoms.

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    • A human respiratory system.
      By: pixelcaos
      A human respiratory system.
    • Exposure to contaminated hay can cause farmer's lung.
      By: Stefano Neri
      Exposure to contaminated hay can cause farmer's lung.