What is pinworm infection?
This infection is caused by a small, white
intestinal worm called Enterobius vermicularis (EN-ter-O-be-us ver-MIK-u-lar-is).
Pinworms are about the length of a staple and live in the rectum of humans.
While an infected person sleeps, female pinworms leave the intestines through
the anus and deposit eggs on the surrounding skin.
What are the symptoms of a pinworm infection?
Itching around the anus,
disturbed sleep, and irritability are common symptoms. If the infection is
heavy, symptoms may also include loss of appetite, restlessness, and difficulty
sleeping. Symptoms are caused by the female pinworm laying her eggs. Most
symptoms of pinworm infection are mild; many infected people have no symptoms.
Who is at risk for pinworm infection?
Pinworm is the most common worm
infection in the United States. School-age children, followed by preschoolers,
have the highest rates of infection. In some groups nearly 50% of children are
infected. Infection often occurs in more than one family member. Adults are less
likely to have pinworm infection, except mothers of infected children. Child
care centers, and other institutional settings often have cases of pinworm
How is pinworm infection spread?
Pinworm eggs are infective within a few
hours after being deposited on the skin. They can survive up to 2 weeks on
clothing, bedding, or other objects. You or your children can become infected
after accidentally ingesting (swallowing) infective pinworm eggs from
contaminated surfaces or fingers.
How is pinworm infection diagnosed?
If pinworms are suspected, transparent
adhesive tape (often called the "scotch tape test") or a pinworm paddle
(supplied by your health care provider) are applied to the anal region. The eggs
become glued to the sticky tape or paddle and are identified by examination
under a microscope. Because bathing or having a bowel movement may remove eggs,
the test should be done as soon as you wake up in the morning. You may have to
provide several samples to your health care provider for examination. Since
scratching of the anal area is common, samples taken from under the fingernails
may also contain eggs. Eggs are rarely found during lab examinations of stool or
urine. At night, the adult worms can sometimes be seen directly in bedclothes or
around the anal area.