The fungus most commonly attacks the feet because shoes create a warm, dark, and humid environment which encourages fungus growth. The warmth and dampness of areas around swimming pools, showers, and locker rooms, are also breeding grounds for fungi. Not all fungus conditions are athlete's foot. Other conditions, such as disturbances of the sweat mechanism, reaction to dyes or adhesives in shoes, eczema, and psoriasis, also may mimic athlete's foot. The signs of athlete's foot, singly or combined, are drying skin, itching scaling, inflammation, and blisters.
Blisters often lead to cracking of the skin.
When blisters break, small raw areas of tissue are exposed, causing pain and swelling. Itching and burning may increase as the infection spreads. Athlete's foot may spread to the soles of the feet and to the toenails. It can be spread to other parts of the body, notably the groin and underarms, by those who scratch the infection and then touch themselves elsewhere. The organisms causing athlete's foot may persist for long periods.