Ringworm is a fungus infection of the scalp or skin. Symptoms include a rash that is often itchy and flaky. Ringworm on the scalp may leave a flaky patch of baldness. On other areas of the skin, ringworm causes a reddish, ringlike rash that may itch or burn. The area may be dry and scaly or it may be moist or crusted. The same fungi that infect humans can also infect animals such as dogs and cats, and infections may be acquired from pets as well as from infected children.
Ringworm is spread by direct contact with a person or animal infected with the fungus. It can also be spread indirectly through contact with articles (such as combs or clothing) or surfaces which have been contaminated with the fungus. A child with ringworm is infectious as long as the fungus remains present in the skin lesion. The fungus is no longer present when the lesion starts to shrink.