Histoplasmosis

What is histoplasmosis?

Histoplasmosis is a disease caused by infection with the fungus Histoplasma. In some places, Histoplasma lives in the soil or other environments, particularly areas that contain bird or bat droppings. In some places, Histoplasma lives in the soil or other environments, particularly areas that contain bird or bat droppings. People and animals can get histoplasmosis after breathing in fungal spores from the air.

Where does it come from?

Histoplasma thrives in soil or other environmental material containing bird or bat droppings. Histoplasma can be found in many countries around the world. In the US, Histoplasma is mainly found in central and eastern states, especially areas around the Ohio and Mississippi River valleys, but it can likely live in other parts of the country as well. CDC produces a map of the known and estimated distribution of Histoplasma. The full extent of where the fungus lives is unknown. There is some evidence that Histoplasma may live and grow in areas further west than it has previously been detected in the US. Because of this concern for the possibility of Histoplasma in WA, DOH is monitoring for reported human cases or environmental detections. To-date, Histoplasma has not been detected in soil in Washington. However, soils around the state are not routinely tested for the presence of Histoplasma.

How is it spread?

People can get histoplasmosis by breathing in fungal spores from the air. Histoplasmosis risk increases with activities that disturb soil, particularly soil that contains bird or bat droppings. Activities such as landscaping, cleaning chicken coops, exploring caves, remodeling old buildings, or other activities that disturb soil can increase the risk of histoplasmosis. Histoplasmosis is not spread from person-to-person or person-to-animal.

How can we prevent histoplasmosis?

  • Prevent accumulation of bird or bat droppings in and around your home, by ensuring homes are sealed to exclude birds or bats.
  • Avoid disturbing material where there are bird or bat droppings.
  • Large amounts of bird or bat droppings should be cleaned up by professional companies specializing in the removal of hazardous waste.
  • If you must remove accumulated bird or bat droppings, spray the area with water from a spray bottle first to reduce dust, and wear disposable gloves and an N95 mask while cleaning.
  • People at high risk of severe disease, including people with weakened immune systems, should avoid activities known to be associated with histoplasmosis, such as disturbance of accumulated bird or bat droppings, cleaning chicken coops, exploring caves, or remodeling old buildings.

What is the treatment?

Antifungal medication is used to treat histoplasmosis in patients with severe disease requiring treatment.

How soon do symptoms appear?

Most infections cause no symptoms or are mild. Most people who get sick will recover on their own without medication. Symptoms appear 3 to 17 days after breathing in the fungus. Symptoms of histoplasmosis include:

  • Fever
  • Cough
  • Fatigue
  • Chills
  • Headache
  • Chest pain
  • Body aches

People with weakened immune systems, infants, and older adults (age 55 and older), are at higher risk of severe disease. Severe disease can include long-term lung infection, or disease can spread to other parts of the body such as the brain and spinal cord (disseminated histoplasmosis).

Where can I get more information?

For more information call Communicable Disease Epidemiology, 206-418-5500 or toll-free 877-539-4344.

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