Signs and Symptoms:
Pinworm is an intestinal infection caused by tiny parasitic worms measuring about 1/2 inch in length (about 1 cm). Other names for a pinworm infection are "seatworm infection," "threadworm infection," "enterobiasis," or "oxyuriasis."

Sometimes these worms can actually be seen in the area around a child's rectum or in the stool. They may have the appearance of light-colored threads on the move. Often a person can have a pinworm infection without having any symptoms, but when symptoms are present, the most common one is itching around the rectum. This itching is usually worse at night and is caused by worms migrating to the area around the rectum to lay their eggs. When a child scratches the itchy area, eczema or a bacterial infection around the rectum can result. In girls, pinworm infection can spread to the vagina and cause a vaginal discharge.

Description:
Pinworm is an intestinal infection by a parasite - a worm called ENTEROBIUS VERMICULARIS. Pinworm infections probably affect about 200 million people across the world, including about 40 million people in the United States and Canada. Of all age groups, school children are most at risk for pinworm infections.

People are infected by unknowingly eating microscopic pinworm eggs. The eggs pass into the digestive system and hatch in the small intestine. From the small intestine, pinworm larvae continue their journey to the large intestine, where they live as parasites - their heads attached to the inside wall of the bowel. About 2 to 4 weeks after the pinworm eggs were originally acquired, adult female pinworms begin migrating from the large intestine to the area around the rectum. There they will lay new pinworm eggs, which trigger itching around the rectum. When someone scratches the itchy area, microscopic pinworm eggs are transferred to their fingers. Contaminated fingers can carry pinworm eggs to many different surfaces, including: bed linens, towels, clothing (especially underwear and pajamas), toilets and bathroom fixtures, drinking glasses and eating utensils, toys, sandboxes, and food. Pinworm eggs are able to live on a surface for 2 to 3 weeks.

Prevention:
You can prevent pinworm infections by reminding your child to wash his hands after using the toilet and before eating. Make sure that your child showers or bathes every day, and changes underwear frequently.

If your child has a pinworm infection, all members of your household will need to be treated with medication. This will help prevent the infection from coming back in most cases.

Incubation:
After pinworm eggs are ingested, it takes about 2 to 4 weeks for itching around the rectum to begin.

Duration:
Pinworm can usually be treated with one dose of medication. After 2 weeks, your child's doctor may repeat the dose.

Contagiousness:
Pinworm infections are contagious. Persons become infected by inadvertently eating microscopic pinworm eggs that can be found on many different surfaces, including: bed linens, clothing, food, drinking glasses, eating utensils, toilet seats, bathroom fixtures, toys, and the sand in sandboxes.

Professional Treatment:
Your child's doctor may ask you to help make the diagnosis of pinworm by placing a sticky piece of cellophane tape against your child's rectum. Pinworm eggs will stick to the tape and can be seen under a microscope in a laboratory.

Your child's doctor will probably give everyone in your family one dose of an anti-worm medicine that will eliminate the pinworm infection. After 2 weeks, your doctor may give a second dose of anti-worm medicine.

Home Treatment:
If your child has a pinworm infection, follow your child's doctor's directions for giving pinworm medicine to everyone in your household. Routine household cleaning measures will help reduce the spread of pinworm infection to the family.

When to Call Your Child's Doctor:
Consider calling your child's doctor if your child complains of an itchy rectum or always seems to be scratching the rectal or genital area. You might also want to consider asking your child's doctor about pinworms (among other causes) if your child seems to have trouble sleeping or has begun to wet the bed.