" Ringworm, despite its name, is not caused by a worm but a fungus. It causes an itchy rash. Jock itch and athlete’s foot are both forms of ringworm as well. Symptoms include a very itchy rash, often, but not always, in the shape of a ring. To diagnose, doctors may look at a scraping of the rash but most likely, a doctor can diagnose by just looking. Ringworm can be treated with over the ...