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What you need to know about: Pinworms/ Pinworm infections

What are pinworms? What do pinworms cause?

Pinworm infections are common intestinal infections caused by the parasite Enterobius vermicularis .

What are the symptoms of pinworm infection?

Most symptoms of pinworm infection are mild; many infected people have no symptoms. When present, the main symptom is rectal itching, especially intense at night or early morning. Other possible symptoms include: irritability, restlessness, abdominal pain, and inflammation of the vaginal area.

How common are pinworm infections?

This is an easily transmissible infection that is very common in families with small children.

Pinworm is the most common worm infection in the United States. Experts estimate that one in ten people throughout the world become infected with pinworms.

How do people get pinworms?

Adult pinworms live in the large intestines. When ready to lay eggs, the female crawls out of the anus and lays the eggs on the perianal (that is, the area around the anus) skin. A single female can produce more than 10,000 eggs. The eggs are spread when the person scratches that area and transfers the eggs into the mouth or to another person. Contaminated bed linens, food, clothing, and other articles can indirectly transfer the eggs. Eggs can live in an indoor environment for about two weeks.

How do I protect my family from pinworms?

Since the infected person's hands will, invariably, be contaminated with eggs, teaching small children good handwashing habits, particularly before eating and after using the toilet, helps prevent reinfection and spreading the eggs to others. 

When someone in the family has been diagnosed with pinworms, all the sheets, blankets, towels, and clothing in the house should be washed in hot water and dried in the hottest possible setting. Everyone's fingernails (which might hold the worm eggs) should be carefully cleaned and cut short. Clean and vacuum living and sleeping areas weekly for the next one to two weeks after treatment.

How do I protect others from pinworms?

When a child is diagnosed with a pinworm infection, notify his or her daycare center. The facility will inform you about the policies regarding attending daycare and pinworm infection.

How are pinworm infections diagnosed?

Because female pinworms lay their eggs during the early morning hours, it is the child's parent who must examine the perianal skin for signs of infection.  Eggs on the perianal skin can be detected by using a piece of cellophane tape attached to a wooden applicator stick, sticky side out.  The tape is then pressed against the perianal skin and later examined for eggs.  This is best done as soon as a child awakens. Adult worms can also be seen in the perianal area. The child's skin can be checked with a flashlight during the night and first thing in the morning. Look for white, wiggling threads.

How are pinworm infections treated?

In children over age two, treatment usually includes either mebendazole (Vermox) or Pin-X (pyrantel pamoate), an over-the-counter alternative to Vermox that is available as a liquid. Physicians disagree about whether or not to treat all family members. Some physicians choose to treat the family members only in persistent cases. Consult your healthcare provider for the best course of treatment.

Pinworms (Enterobiasis) ICD-9 127.4; ICD-10 B80