Lillian Dustin, age 15, of Bessemer, Ala., for her question:

WHAT CAUSES RINGWORM?

Ringworm is a skin disease caused by fungi or tiny plants. Itching is a common symptom.

The disease is highly infectious. Children are especially susceptible to the type of ringworm that grows on the scalp. Sometimes children contract it from other students in their school or even from dogs or cats.

A type of ringworm found on the toes is commonly called athlete's foot.

Common ringworm of the skin starts as a small red spot and grows larger with the eruption sometimes appearing as a red, scaly ring.

Doctors usually treat ringworm with local applications of fungicidal compounds.