Globally, athletes foot affects about 15% of the population. Males are more often affected than females. It occurs most frequently in older children or younger adults. Historically it is believed to have been a rare condition that became more frequent in the 20th century due to the greater use of shoes, health clubs, war, and travel. Signs and symptoms
Athletes foot is divided into four categories or presentations: chronic interdigital, plantar (chronic scaly; aka "moccasin foot"), acute ulcerative, and vesiculobullous. "Interdigital" means between the toes. "Plantar" here refers to the sole of the foot. The ulcerative condition includes macerated lesions with scaly borders. Maceration is the softening and breaking down of skin due to extensive exposure to moisture. A vesiculobullous disease is a type of mucocutaneous disease characterized by vesicles and bullae (blisters). Both vesicles and bullae are fluid-filled lesions, and they are distinguished by size (vesicles being less than 5–10 mm and bulla being larger than 5–10 mm, depending upon what definition is used).Athletes foot occurs most often between the toes (interdigital), with the space between the fourth and fifth digits (the little toe and the fore toe) most commonly affected. Cases of interdigital athletes foot caused by Trichophyton rubrum may be symptomless, it may itch, or the skin between the toes may appear red or ulcerative (scaly, flaky, with soft and white if skin has been kept wet), with or without itching.
Further scratching may remove scabs, inhibiting the healing process. Scratching infected areas may also spread the fungus to the fingers and under the fingernails. If not washed away soon enough, it can infect the fingers and fingernails, growing in the skin and in the nails (not just underneath). After scratching, it can be spread to wherever the person touches, including other parts of the body and to ones environment. Scratching also causes infected skin scales to fall off into ones environment, leading to further possible spread. When athletes foot fungus or infested skin particles spread to ones environment (such as to clothes, shoes, bathroom, etc.) whether through scratching, falling, or rubbing off, not only can they infect other people, they can also reinfect (or further infect) the host they came from. For example, infected feet infest ones socks and shoes which further expose the feet to the fungus and its spores when worn again.The ease with which the fungus spreads to other areas of the body (on ones fingers) poses another complication. When the fungus is spread to other parts of the body, it can easily be spread back to the feet after the feet have been treated. And because the condition is called something else in each place it takes hold (e.g., tinea corporis (ringworm) or tinea cruris (jock itch)), persons infected may not be aware it is the same disease.