According to Dr. Johanna Youner, an APMA podiatrist and spokesperson practicing in New York City, athlete's foot is a fungal infection of the skin on your foot that thrives in warm, moist areas. Your risk for getting athlete's foot increases if you wear closed shoes - especially if they are plastic lined, keep your feet wet for long periods of time, and have increased sweating. Athlete's foot is also contagious and can be passed via surfaces like pool decks and showers.
What to do: "To avoid this common summer condition, dry your feet thoroughly, especially between the toes, before putting on your shoes and socks," Dr. Youner recommends. "Change your socks during the day if they become saturated with sweat, and add a powder like cornstarch into your daily routine after showering to keep your feet dry and prevent infection."