What Fungus Causes Athlete's Foot?

Human dermatophytes, a species of fungus, cause athlete's foot. You can get it from touching the sores of someone with ringworm, or from the soil or pets.

Athlete’s foot (tinea pedis) is a contagious fungal infection caused by a ringworm. Ringworm is not actually a worm. It is so-named because it can cause a ring-shaped, red, itchy rash on the skin.

Athlete’s foot affects the skin as well as the fingernails and toenails. The symptoms of athlete’s foot appear between 4 to 14 days after coming into contact with the fungi that cause ringworm.

Symptoms of athlete’s foot include

• Ring-shaped rash
• Itching
• Skin redness
• Scaly, cracked skin
• Red, swollen, peeling, itchy skin between the toes 
• Soles, heels, and toenails may also be affected
• Skin on the feet may blister in severe cases

Athlete’s foot (tinea pedis) is most often caused by human dermatophytes, a type of fungus transmitted by direct contact with human ringworm sores. Ringworm may also be acquired from the soil or through exposure to animals (commonly household pets).

Risk factors for developing athlete’s foot include:

• People who have a weakened immune system (such as from HIV/AIDS, cancer, chemotherapy, diabetes, or certain medications)
• Use of public showers or locker rooms
• Athletes involved in contact sports, such as wrestling
• Excessive sweating in tight shoes 
• Close contact with affected animals such as household pets
• Working with soil that has ringworm fungus
• Living in a warm, humid climate
• Close contact with a person who is infected
• Sharing bedding, towels, or clothing with a person who is infected

Athlete’s foot (tinea pedis) is often diagnosed with a physical examination of the affected skin. 

Tests that may be indicated to diagnose athlete’s foot include:

• Skin scraping to be examined under a microscope or sent to a laboratory for a fungal culture
• Ultraviolet light
  • Can only diagnose two species: Microsporum canis and audouinii 

Treatment for athlete's foot (tinea pedis) includes:

• Over-the-counter antifungal products to kill the athlete’s foot fungus
• Chronic or extensive tinea pedis may require oral antifungals such as terbinafine, itraconazole, or fluconazole
• Chronic tinea pedis may require foot powder or talcum powder to prevent skin softening

To prevent athlete's foot (tinea pedis)

• Do not share clothing, sports equipment, or towels with other people
• Always wear slippers or sandals at the gym, local pool, or other public areas (including the shower)
• Wash thoroughly with soap after any sport involving skin-to-skin contact
• Avoid tight-fitting clothing
• Wear a clean pair of socks every day
• Put socks on before putting on underwear so the infection does not spread to other parts of the body
• Keep the skin clean and dry and always dry off completely after bathing
• For pets: if your pet has patches of missing hair or a rash take them to the vet because it could be a sign of a tinea infection