Prevention for Histoplasmosis:

It's difficult to prevent exposure to the fungus that causes histoplasmosis, especially in parts of the country where the disease is widespread. Even so, these steps can help reduce the risk of infection:

• Spray contaminated soil. Before you work in or dig soil that's likely to harbor H. capsulatum, spray it thoroughly with water. This can help prevent spores from being released into the air. Spraying chicken coops and barns before cleaning them also can reduce your risk.
• Use an effective face mask. This is the best way to protect yourself from soil-borne organisms if you must work in contaminated areas or in caves known to harbor bats. The National Institute for Occupational Safety and Health (NIOSH) recommends using Part 84 particulate respirators certified by NIOSH.