(*PDF version) for printing. What is Histoplasmosis?
Histoplasmosis is an infectious disease caused by inhaling
spores of a fungus called Histoplasma capsulatum. Who gets
histoplasmosis? Anyone who is present near dust-producing
activities where material contaminated with H. capsulatum
becomes airborne can get histoplasmosis if enough spores are
inhaled. Infants, young children, and older persons, in
particular those with chronic lung disease, are at increased
risk for developing symptomatic histoplasmosis. People with
weakened immune systems are at greatest risk for developing
severe and disseminated disease. H. capsulatum grows in soil
throughout the world. In the United States, it is more common in
the central and eastern states, especially along the valleys of
the Ohio, Mississippi, St. Lawrence rivers, and the Rio Grande.
The fungus seems to grow best in soils with a high nitrogen
content, especially those contaminated with bird manure or bat
droppings. How is histoplasmosis spread? Disturbances of conta