These fungi often cause diseases in the plants and animals they infect. The most common fungal diseases in people are skin infections, such as ringworm or athlete's foot. These conditions can be caused by a number of fungi, including species in the groups Trichophyton, Microsporum, and Epidermophyton. Other fungi that normally live harmlessly in the body can sometimes cause disease. For example, fungi in the Candida group, which commonly inhabit the mouth, bowel, or vagina, can cause a variety of disorders, including a disease of the throat called thrush.
Many fungal diseases affect internal organs and organ systems.
The most common of these systemic diseases include histoplasmosis, blastomycosis, and coccidioidomycosis. These three diseases attack the lungs and usually are not serious. However, these same disorders can occasionally be deadly in otherwise healthy people, especially those who lack natural resistance because of AIDS or other diseases. In these patients, the fungi may travel through the body to the bones, kidneys, and central nervous system. Doctors may prescribe antifungal creams or ointments to treat fungal diseases of the skin.