Pinworm Disease

Infection with pinworms usually causes itching around the anus, and irritability, often because of disrupted sleep. Some individuals with pinworm infection may not have any symptoms. Symptoms are caused by the female pinworm laying her eggs on the skin. After ingesting a pinworm egg, it takes about 1 to 2 months or longer for an egg to grow to an adult who can lay eggs around the anus.

You get the disease by ingesting (eating) pinworm eggs. The eggs travel to the intestines where they hatch and mature. The mature worms then travel to the anus, where they deposit a new batch of eggs, usually at night. Contamination of the hands, clothing, and bedding can take place at this time. Transmission occurs when the eggs are transferred to a person’s mouth, by hand from anus-to-mouth, or indirectly, by putting pinworm-contaminated items into the mouth.

There is no laboratory test available to diagnose a pinworm infection. Stool samples are not recommended because pinworm eggs and worms are not common in stool. There are three techniques to diagnose pinworm infections. The first is to look for the worms near the anus 2 to 3 hours after the infected person is asleep. The second is to touch the anus with clear tape first thing in the morning to possibly collect eggs. The eggs will be visible on the tape under a microscope. The tape test should be done on three consecutive mornings. The third option is to look at samples from under the fingernails with a microscope. An infected person could have picked up eggs from scratching.

Antiparasitic medications prescribed by a doctor are effective in pinworm infections. Household and intimate contacts may also require treatment. Reinfection is common and several treatments may be necessary if exposure to the parasite continues.