Pinworms in Children and Adults: Sources of Infection

Pinworms can cause anal itching and difficulty sleeping or no symptoms at all

Pinworms are small parasitic worms that live in a person’s colon and rectum and lay eggs around the anus. Pinworm infection is the most common type of worm infection in the United States, and it occurs most often in children and people who live in group settings, like nursing homes.

Pinworm eggs can cause anal itching and restlessness at night, but overall the infection is generally minor. 

Continue reading to learn more about pinworms, including how they're acquired and how to tell if you or your child has this type of infection. 

Girl taking medicine at home

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Common Symptoms of Pinworms

The most common symptom of pinworms is anal itching, usually at night. At night, female pinworms come out of the colon to lay their eggs on the anus. This causes itchiness that can lead to restlessness during sleep.

Children

Pinworm infection is most common in school-aged children, making it a fairly common childhood illness. The symptoms of pinworms in kids can include:

  • An itchy anus
  • Trouble sleeping
  • Restlessness at night
  • Sore, red anal area
  • Small white worms around the anus
  • Eggs on the anus, especially in the morning

Adults 

Adults experience the same symptoms of pinworms that kids do. Adults might also experience nervousness or a loss of appetite in severe cases.

Anal and Vaginal 

Most often, people experience pinworms in the anal area. Pinworms live in the colon or rectum and lay their eggs by the anus. However, people can also experience additional symptoms if they have pinworms in the vagina. The additional symptoms can include:

  • Vaginal itching
  • Changes to vaginal discharge, including discharge in children

Where Do Pinworms Come From?

A person gets a pinworm infection when they unintentionally swallow pinworm eggs. The eggs hatch in the digestive tract, and one to two months later females start laying their eggs on the anus, leading to itching.

Transmission 

Pinworm transmission happens via the fecal-oral route, When pinworm eggs travel from an infected person’s anus to another person’s mouth. This can happen in a few different ways:

  • Directly by hand: For example, a parent or caregiver who wipes the bottom of someone with pinworms might get eggs onto their hands and risk swallowing those eggs if they don’t properly wash their hands. 
  • Indirectly through surface contact: Pinworm eggs can live for two to three weeks on bedsheets, bathroom surfaces, doorknobs, and other surfaces around a building. If you come into contact with these eggs, you may accidentally ingest them. 
  • Through the air: Occasionally, pinworm eggs can become airborne and be breathed into the mouth. This can happen when a person is shaking out sheets or changing bedding. 

Contagiousness 

Since pinworms are highly contagious, they often spread through family homes, daycares and other institutions like nursing homes. If someone in your family is being treated for pinworms, everyone else in the household should be treated too, even if they don’t have symptoms.

Risks of Untreated Pinworms

Pinworms generally have few risks. However, severe infections can cause additional symptoms including:

  • Weight loss
  • Loss of appetite
  • Nervousness and restlessness
  • Belly pain
  • Nausea

Over-the-Counter (OTC) Pinworm Treatment

There is one over-the-counter pinworm treatment available. It’s called pyrantel pamoate, a medication used to treat pinworms and other intestinal worms, including roundworms and hookworms.  To treat pinworms, the medication is taken as one dose. Then, another dose is taken two weeks later. The treatment kills pinworms, but doesn’t always kill all their eggs.

When Do Symptoms Warrant Prescription Treatment?

There are two types of prescription medications used to treat pinworms. If you or your children have pinworms, it’s best to talk with your healthcare provider about whether an over-the-counter or prescription treatment is best. The two prescriptions that treat pinworms are:

  • Vermox (mebendazole)
  • Albenza (albendazole)

Safety of Pinworm Treatments

Although pinworm infections often occur in children and their caregivers, there’s not solid research about the safety of pinworm treatments for children under the age of 2, pregnant people, and people who are breastfeeding. Talk with your healthcare provider if you or your child fall into one of these groups.

Hygiene and Disinfecting the Home

If you’re fighting a pinworm infection, these tips can help you keep the infection from spreading:

  • Wash your hands frequently: Supervise young children to make sure they’re washing their hands with soap and water after using the bathroom. 
  • Keep nails short: Nails can trap pinworm eggs. Do not bite your nails. 
  • Change bed clothes and underwear first thing in the morning: Since these items might be contaminated with eggs, do not shake them out. Instead, carefully ball them up and place them in a washing machine. Wash and dry the items on high heat to kill any eggs. 
  • Shower first thing in the morning: This can remove eggs from the skin. 
  • Don’t bathe with others: This can spread pinworms. Take showers during treatment and two weeks after to avoid spreading eggs onto the bathtub. 
  • Don’t scratch: Although a pinworm infection can make your bottom itchy, scratching can spread eggs. If you must scratch or catch your child scratching, wash your hands thoroughly afterward. 

Testing to Diagnose Pinworms

You can diagnose pinworms in yourself or a loved one at home, although you may need to go to a healthcare provider for confirmation. Here’s how:

The Flashlight Test

If you suspect that you or a loved one has pinworms, use a flashlight to carefully examine their anus for three nights in a row. Look for pinworms, which are typically white and about the size of a staple. They might look like threads.

You can also look for redness or irritation, which can indicate a pinworm infection. 

The Tape Test

This test is considered the best way to look for pinworms. Here’s how to do it:

  • Conduct the test first thing in the morning, before showering or wiping. For best results, do the test three days in a row, so that you have three separate samples. 
  • Cut a 1-inch strip of cellophane or scotch tape and gather a plastic bag with a seal. 
  • Press the tape over the anus firmly. Hold it for three seconds. 
  • Put the tape in the bag, and seal it well. 
  • Wash your hands thoroughly. 
  • Bring the bag to your healthcare provider. They will examine the tape to look for signs of pinworm eggs. 

Sometimes, your healthcare provider will provide you with a pinworm test kit. In that case, follow the directions on the kit. 

How Long Does It Take to Get Rid of Pinworms?

It takes about two weeks to get rid of pinworms. The initial dose of medication will kill most worms, but not all the eggs. Because of that, it’s recommended that you take another dose of medication, two weeks after the first. 

In order to get rid of pinworms quickly, follow these steps:

  • Treat everyone in the house, even if they don’t have symptoms. 
  • Wash bedding in hot water to kill eggs. 
  • Take a second dose of medication, two weeks after the first. 

Reinfection From Pinworms 

The best way to avoid reinfection is by washing your hands and those of your children frequently with soap and water. In addition, treating the entire household, washing underwear frequently, and showering first thing in the morning can all help reduce risk. 

Summary

Pinworms are the most common worm infection in Americans. They mostly impact children, their caregivers, and people who live in group settings. An itchy anus, especially at night, is the most common symptom of pinworms, although some people with the infection have no symptoms at all. If you believe you or your loved ones have pinworms, talk with your healthcare provider about the best treatment.

Typically, the whole household will need to get two doses of medication: one as soon as possible, and one two weeks later. Washing your hands frequently and doing laundry with hot water can also help you avoid reinfection. 

6 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Centers for Disease Control and Prevention. Pinworm infection FAQs.

  2. Nemours. Pinworm infection (for parents).

  3. New York State Department of Health. Pinworm infection.

  4. MedlinePlus. Pyrantel. Sept. 15, 2017.

  5. Centers for Disease Control and Prevention. Parasites - Enterobiasis (also known as Pinworm Infection). August 28, 2019.

  6. MedlinePlus. Pinworm test.

By Kelly Burch
Kelly Burch is has written about health topics for more than a decade. Her writing has appeared in The Washington Post, The Chicago Tribune, and more.