(Tinea Pedis · Foot Ringworm)

In this condition factsheet:

• The facts on Athlete's Foot


• Causes of Athlete's Foot


• Symptoms and Complications of Athlete's Foot


• Diagnosing Athlete's Foot


• Treating and Preventing Athlete's Foot

The Facts on Athlete's Foot

Athlete's foot, known as dermatophytosis of the foot or tinea pedis ("foot fungus"), is a common skin infection that affects the feet. You don't have to be an "athlete" to get it.

Around 5% of Canadians have a foot infection at any given time, including athlete's foot. Men tend to be affected more than women, and children more than adults.

There are 4 types of athlete's foot: moccasin-type, vesicular or blistered, interdigital (between the toes), and ulcerative.

Causes of Athlete's Foot

Athlete's foot is caused by a fungal infection. The fungi that infect human feet live on the skin, specifically on skin proteins called keratin. These fungi thrive in hot, tropical climates. Wearing tight, non-breathing footwear allows the fungi to flourish and cause athlete's foot. The fungal organisms easily spread from one person to another in moist places where people walk barefoot, such as gym locker rooms and swimming pools. Cuts or blisters on the feet make it easier for these organisms to cause an infection.

Interdigital athlete's foot is the most common type, usually starting between the 4th and 5th toes. Interdigital and moccasin-type athlete's foot are commonly caused by the fungus T. rubrum. Vesicular or blistered athlete's foot is believed to be due to an allergic reaction to fungal organisms, causing blisters to form. Ulcerative tinea pedis occurs in severe cases and can affect large areas, and there's usually a secondary bacterial infection on top of the fungal infection.

Symptoms and Complications of Athlete's Foot

Athlete's foot usually forms between the fourth and fifth (smallest) toes or third and fourth toes, producing skin cracking, white and soggy toes, scaling, and itchiness. The infection can spread to the soles of the feet. It's made worse by sweaty feet and wearing tight socks or shoes that trap moisture. If a bacterial infection sets in on top of it, the skin will ooze, burn, and smell.

Moccasin-type athlete's foot doesn't cause itching or inflammation. The entire sole and heel become dry and flaky with loose, white scales that appear in a moccasin-like pattern. Sometimes the toenails can also become infected, which makes it more difficult to treat.

People with vesicular or blistered athlete's foot suffer from sore, fluid-filled blisters that occur between the toes and on the arch and sides of the foot. These blisters form in response to an allergic reaction to the fungi causing the athlete's foot.

Interdigital tinea pedis is the most common type and presents as maceration (softened tissue caused by soaking) and scales in the web spaces between the toes. This type may become ulcerative when a secondary bacterial infection occurs. Symptoms include painful ulcers between the toes, which often take a long time to heal.

Tinea pedis can lead to infections (cellulitis) in the feet or legs. This can be particularly worrisome in people who have diabetes or chronic vascular diseases.