What are pinworms?
Pinworms are small, white, threadlike roundworms (about ½ inch in length) that live in the large intestine and come out to lay eggs around 9-10 PM at night. There are very few other worms that inhabit the human body that have these 3 characteristics: small, white and symptomatic at night. Pinworm infections are annoying but not serious. They cause no serious complications.
What are symptoms of pinworms?
Pinworms cause intense itchiness around the anus or the vagina, especially at night. This occurs when the worms exit the body to lay worms. Up to 10,000 eggs can be laid at any one time. The itchiness is caused by the local reaction of the body to the eggs.
How is pinworm contracted?
Pinworm eggs must be ingested and then they make their way through the GI tract over a 1-2 month period before exiting at the anus. Pinworms are spread directly or indirectly by sharing toys, clothing, toilet seats or baths. Pinworm eggs are microscopic and can float in the air for up to 2 weeks.
How long is a person contagious?
The adult pinworms die shortly after laying their eggs. The eggs are contagious for 2-3 weeks and the disease spreads when picked up by children who touch their bottoms and then touch a food or surface that is touched by another person.
How is pinworm diagnosed?
For children in diapers, the diagnosis is easy because you can see the white worms mixed into the stool. For toilet trained children, it is more complicated to make a diagnosis. The classic test is the scotch tape test where clean scotch tape is placed over the anus and removed in the morning, brought to the office and placed under a microscope. This is cumbersome and difficult to accomplish for almost any parent and we do not recommend this approach. Most pediatric providers will treat based on the symptoms of severe itchiness only at night.
What is the treatment?
Pyrantal Pamoate is an over the counter medication that is given based on body weight. The two brand names currently available are Pin-X and Reese’s Pinworm Medicine. These are also not approved for children under 2 years and should be repeated in 2 weeks. Treatment is almost 100% effective. Most new cases are recurrences that come from children reinfecting themselves with eggs that are floating in their environment. When there has been a recent recurrence, you should treat 3 times, with treatment doses spread every 2-3 weeks.
What should be done in addition to treatment?
There are many things that can be done to prevent recurrence:
- Bathe in the morning to reduce egg contamination. Avoid bathing children together.
- Dress your child in tight underwear both day and night. Change and wash the underwear every day. Also, frequent changing of sleepwear is recommended. Wash clothes in a hot cycle.
- Be sure to wash everyone’s fingers especially before eating. Adults with pinworm should not be food preparers.
- Help your child to avoid scratching his or her buttocks.
- Keep fingernails short and discourage children from nail biting.
- Clean the bedroom floor by damp mopping or vacuuming. Avoid sweeping as that may spread the eggs.
- Wash bedding because the eggs can survive on linens for up to two weeks.
- While bathing, personal hygiene and keeping clothes and linens clean helps minimize infection, keeping the house spotless won't really make much of a difference. This has puzzled many parents who question how pinworm infections could thrive when they were keeping an immaculately clean house. The eggs do not live on all kinds of surfaces. They can persist on things like underclothes but are not likely to persist on a rug or countertop. Pinworms require very close contact with the human body.
What about treating siblings and other family members?
When exposed to pinworms and especially in cases where more than one family member has it, we recommend treating all household members. Pyrantal Pamoate is not recommended for children under 2 years old, although infection for them is not common.