what causes ringworm in adults
Overview When to see a doctor. See your doctor if you have a rash on your skin that doesn't begin to improve within two weeks. You may need prescription medication. Causes. Ringworm is a contagious fungal infection caused by mold-like parasites that live on the cells in the outer layer of your skin. It can be spread in the following ways: Human to human. Ringworm often spreads by direct, skin-to-skin contact with an infected person.