Cause

Pinworm infections are usually caused by swallowing the eggs of the pinworm (Enterobius vermicularis) after coming in contact with an infected person or with an object that has eggs on its surface. Infection can also be spread when a person inhales airborne eggs, but this is rare. In rare cases, pinworm infection persists because eggs hatch outside the anus and the young worms crawl back inside the body.

Symptoms

Pinworms do not usually cause any symptoms beyond minor itching around the anus. Many people with pinworm infections have no symptoms and may never be aware of the infection. The infection can go away without treatment.

The most common symptoms of pinworm infection in children include:

• Itching around the anus. For most children this symptom is mild. Only in rare cases do children have very severe itching.
• Restless sleep (itching is often worse at night).

Other possible symptoms that may be present but are much less common include:

• Itching in the genital area.
• Pain or burning when urinating.
• Worms in stool (rarely seen).
• Abdominal pain (rare, except when complications develop).

The above symptoms may result in anxiety.

Other conditions with similar symptoms include hemorrhoids and infections caused by other intestinal parasites (Ascaris, Trichuris, or tapeworms).