Causes

Athlete's foot is caused by the same type of fungi (dermatophytes) that cause ringworm and jock itch. Damp socks and shoes and warm, humid conditions favor the organisms' growth.

Athlete's foot is contagious and can spread through contact with an infected person or from contact with contaminated surfaces, such as towels, floors and shoes. You can also spread it from the foot to other parts of the body, especially if you scratch or pick the infected parts of your foot.