Hypersensitivity Pneumonitis

Hypersensitivity pneumonitis is a disease in which your lungs become inflamed when you breathe in certain dusts to which you are allergic. These dusts contain fungus spores from moldy hay or the droppings of birds.

The disease most often occurs in people who work in places with high levels of dust that contain fungus spores from mold. The most common type of hypersensitivity pneumonitis is farmer's lung, which can develop from exposure to moldy hay, straw and grain.

There is no cure or effective treatment for hypersensitivity pneumonitis. The good news is that the disease can be completely reversed in its early stages if you avoid the dust that causes it.