Histoplasmosis is a spore that can be found in bat droppings. When droppings are disturbed or cleaned up these spores can become airborne. If breathed in, the spores can develop a fungus in the lungs. This can cause breathing problems and make people very sick. Great care should be used when cleaning up bat droppings including wearing a respirator and gloves. Droppings can be sprayed with bleach and water to keep spores from becoming airborne.