Ringworm (tinea corporis) is a common infection of the skin and hair of children.
Interestingly, ringworm is not actually caused by a worm. It is caused by a number of different types of fungi and is usually spread from other infected children or sometimes from infected animals.
The infection begins as a red sore, which slowly grows larger and becomes scaly, itchy and may develop a red ring around it.
Ringworm on the skin is easily treated with an antifungal cream, although it may require treatment for 2-4 weeks for the infection to totally clear up.
If the infection is on the scalp (tinea capitis), it can also cause hairs to break off, creating bald spots. Infection on the scalp is more difficult to treat and requires an oral antifungal medication, such as Griseofulvin for 6-8 weeks. Keep in mind that higher than typical doses are often required now when using this antifungal medicine and they absorbed best when given with a high fat meal.
Using an antifungal shampoo daily, such as Nizoral (ketoconazole), or a shampoo with selenium sulfide (Selsun) twice weekly, may also help clear the infection sooner, and will at least make you less contagious to others.
Selenium sulfide should also be used twice weekly in close contacts of someone with tinea capitis to prevent them from becoming an asymptomatic carrier (people who are infected, don't have symptoms, but are contagious to others).
Although not always necessary, testing can be done to confirm a diagnosis of ringworm, including a KOH test and a simple fungal culture.
It is usually not necessary to keep your children out of school or daycare when they have a ringworm infection.