What is histoplasmosis?

Histoplasmosis is an infection caused by a fungus called Histoplasma capsulatum. It usually affects the lungs. A person gets histoplasmosis by breathing in the spores of the fungus. It is not spread from one person to another. An infected person may feel generally sick and have a fever, cough and chest pains. But many people who get infected do not have any symptoms. People with a healthy immune system usually recover from a mild infection without treatment. But in people with a weak immune system, such as those with cancer or AIDS, histoplasmosis may spread beyond the lungs to other organs. This is called disseminated disease. People with a severe infection or disseminated disease are treated with antifungal medicines.

Histoplasmosis is a disease sometimes associated with bats. Its symptoms vary greatly, but the disease primarily affects the lungs. Occasionally, the infection can spread to other organs. When this happens, it can be fatal if untreated.

Histoplasmosis is a disease caused by a fungus that may be associated with accumulations of bird or bat droppings (also known as guano). Histoplasmosis can contaminate the guano, and when areas with heavy accumulations of guano are disturbed, the infectious fungal spores can be released and aerosolized.

The fungus that causes histoplasmosis can be found throughout the world, including certain areas of the United States, such as the Ohio and Mississippi River valleys. The fungus may also be present in places that harbor large populations of bats, including caves.

Many infected persons do not have any symptoms of infection. Sometimes, antifungal medications are used to treat persons with histoplasmosis, particularly if they have severe or prolonged symptoms.

The presence of the CDC logo and CDC content on this page should not be construed to imply endorsement by the US Government of any commercial products or services, or to replace the advice of a medical professional. The mark “CDC” is licensed under authority of the PHS.