Histoplasmosis is caused by the reproductive cells (spores) of the fungus Histoplasma capsulatum. The spores are extremely light and float into the air when dirt or other contaminated material is disturbed. Even if you've had histoplasmosis in the past, you can still get the infection again. However, if you contract histoplasmosis again, the illness will likely be milder than the initial infection.

The histoplasmosis fungus thrives in damp soil that's rich in organic material, especially the droppings from birds and bats. For that reason, it's particularly common in chicken and pigeon coops, old barns, caves and parks. Histoplasmosis isn't contagious, so it can't be spread from person to person.

Feb. 08, 2012