Acute pulmonary histoplasmosis is a respiratory infection caused by inhaling the
Causes, incidence, and risk factors
Histoplasma capsulatum, the fungus that causes histoplasmosis, is found in the Central and Eastern United States, Eastern Canada, Mexico, Central America, South America, Africa, and Southeast Asia. It is commonly found in the soil along river valleys. It gets into the soil mostly from bird and bat droppings.
You can get sick when you breathe in spores produced by the fungus. Every year, thousands of people worldwide are infected, but do not become seriously sick. Most patients have no symptoms or have only a mild flu-like illness and recover without any treatment.
Risk factors include traveling to or living in the Central or Eastern United States near the Ohio and Mississippi River Valleys, and being exposed to the droppings of birds and bats. This threat is greatest after an old building is torn down, or when exploring caves. Having a weakened immune system increases your risk for getting or reactivating the disease, and for having more and worse symptoms.