Athlete’s foot is a contagious fungal infection that affects millions each year but leaves plenty of those patients too embarrassed to come forward. The itchy redness, flaky or peeling skin can cause burning or an uncomfortable sensation, but patients may wait weeks before seeking help.

“I know I personally have dealt with it before in my life and it is not fun,” Dr. Brad Schaeffer, of TLC’s hit show “My Feet Are Killing Me,” told Fox News. “It can be really itchy and it can be red, and it can create little cuts in the skin. It’s painful.”

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The fungus thrives in moist environments, he said, and walking around a gym barefoot or even in your own house can leave you susceptible to infection. The fungus can also spread to other parts of the body if a person touches the affected foot and then touches another area on their person.

Sharing towels, sheets, clothing or shoes with someone who has the infection can also help it spread, according to KidsHealth.org.

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Some patients, he said, may even struggle to put socks and shoes on. But most cases can be easily treated with an ointment or cream which will cure it quickly. Over-the-counter medications typically solve mild cases, although some may require stronger prescriptions.

“You should not go too long without having it looked at,” Schaeffer said, adding that taking proper care of the infection, which is also known as tinea pedis, can bring quick relief.

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To avoid contracting athlete’s foot, keep your feet clean by washing them daily and making sure they are completely dry. Using waterproof shoes in locker rooms and public showers or pool areas can also help protect your feet, as well as switching shoes and sneakers to prevent a build-up of moisture, according to KidsHealth.org.

To see Schaeffer in action, tune into TLC on Thursdays at 10 p.m. ET.