Henry (Hank) Bernstein, D.O. is a Senior Lecturer in Pediatrics at Harvard Medical School and Professor of Pediatrics at Dartmouth Medical School. Formerly the Associate Chief of General Pediatrics and Director of Primary Care at Children's Hospital Boston, he currently is the Chief of General Academic Pediatrics at Children's Hospital at Dartmouth. He has extensive and varied experience as a primary care pediatrician, and is a spokesperson for the news media on a variety of pediatric health care topics, including vaccination, common childhood illnesses, and practical information for caregivers.

Question:

For how long is ringworm contagious?

Answer:

Ringworm is a very common infection on the skin that is caused by a fungus, not a worm as its name suggests. Ringworm is also called tinea, and it has different names depending upon what body part is affected. Jock itch is ringworm of the groin; athlete's foot is ringworm of the foot. Ringworm on the face, torso, arms or legs is called ringworm of the body. It is not a serious disease in otherwise healthy people.

Children generally do not need to be isolated when they have ringworm. Doctors think it stops being contagious within 24 to 48 hours after treatment starts.

Ringworm is spread by direct human-to-human contact, especially skin-to-skin contact. To prevent ringworm, avoid direct contact with anyone who has it. If your child has been in contact with someone with ringworm, look for the beginnings of the rash. Early treatment can be started to stop the spread.

Ringworm appears as one or more red, round, raised patches on the skin. The edges of the spot may be scaly, and most are smaller than an inch in size. There may seem to be clearing in the middle of the area. It can be itchy and feel uncomfortable. It is called "ringworm" because the infection can produce ring-shaped patches on the skin that have red, wormlike edges.

A doctor diagnoses ringworm by looking at the rash and where it is on the body. Sometimes scrapings of the skin are sent to a laboratory. Ringworm can sometimes look like other skin rashes such as contact dermatitis – a reaction of the skin that occurs when skin comes in contact with something like poison ivy.

Ringworm is usually treated with topical medication. In general, the antifungal medicine is applied to the rash twice a day for at least four weeks. Although the skin may improve within the first week, you should continue the treatment for time your doctor prescribes. Antifungal medicines cause mild side effects, if any. If there is no improvement, medication taken by mouth may be needed.