They are tiny, itchy, and can spread like wildfire in a classroom – and at home. No, we aren’t talking about lice.
Sadly, there is another wormy creature that is very contagious but causes issues, not on your head but in your er, anus or butt. They are pinworms.
Just when you thought lice were the most horrifying things that could enter your household, now these?!
Pinworm infections are the most common type of intestinal infection in the United States and are most common in children ages 5 to 10. Pinworms can be a bum … mer (literally!) but they are nothing to be bummed about.
Here’s what to do if pinworms come a-calling.
What are pinworms?
A pinworm is a common name for a tiny, white roundworm infection known as Enterobiasis vermicularis.
“It is the most common helminthic, or parasitic worm, infection that only affects humans,” said Scott Olson, MD, a pediatric infectious disease specialist with Banner Children's. “Helminths are worm-like parasites that can live, feed and reproduce in the human intestine.”
Luckily, pets like dogs and cats can’t be infected, but it affects nearly a billion people worldwide. Most cases are in school-aged children, their family members or caregivers.
Pinworms are sometimes called threadworms because they look like tiny pieces of white thread (usually no bigger than a staple).
How do you get a pinworm infection?
You can become infected with pinworms by accidentally swallowing or breathing in pinworm eggs. When playing, they can be picked up on children’s fingers (especially under their nails).
They can also spread if an infected child scratches their itchy bottom. If your child doesn’t wash their hands after, they can transfer microscopic eggs to any surface they touch. When someone touches that surface and later touches their mouth, they can also become infected.
“Once they are taken in, the eggs live in the intestines until they hatch and mature,” Dr. Olson said. “After a few weeks, adult females migrate or move to the infected person’s perianal skin, or skin around the anus, to lay eggs, which can cause irritation and itching.”
The eggs are resilient and strong. “They can remain infectious up to several days under someone’s fingernails after scratching or up to several weeks on clothes, bedding and toys,” Dr. Olson said.
While anyone can get an infection, children who don’t wash their hands well before eating or after using the bathroom, bite their nails, or who suck their thumb are at an increased risk for infection. People who live in crowded dorms or institutions and work at childcare or daycare facilities are also at greater risk.
What are the symptoms of a pinworm infection?
Tell-tale signs your child has pinworms are an itchy bottom (around the anus or vagina), problems with sleeping due to discomfort or itching, changes in behavior, such as anxiousness and irritability, and weight loss.
However, Dr. Olson said some people might not experience any symptoms.
“Because the parasites aren’t aggressive and don’t cause a large inflammatory response to the gut, some people may not experience any symptoms,” he said.
How do I know if my child has a pinworm infection?
Unfortunately, you can’t do a blood test or a stool (poo) test to confirm pinworms.
The best way of diagnosing is by looking for the worms and eggs with these three options:
- Look in your child’s tushy. Wake your child about one to two hours after they have gone to bed. With a flashlight or headlamp, check around their anus for wiggly, white hair-thin worms.
- Use the tape test. When your child wakes up in the morning, before they use the bathroom, firmly place a piece of transparent tape (Scotch tape or any generic brand will do) around the anus for a few seconds. Then (carefully!) remove the tape and seal it inside a plastic Ziploc bag. Take the tape to your child’s health care provider so they look at it under a microscope.
- Examine their fingernails. Your child’s provider may also take a sample under their fingernails to look under a microscope as the eggs will stick to the tape. If your child is infected and has been scratching, they may have picked up some pinworm eggs under their nails.
What’s the treatment for pinworms?
Most pinworm infections are mild and easy to treat. There are several over-the-counter (OTC) and prescription anti-parasitic medications that can be taken by mouth for treatment.
Three oral drugs are primarily used: mebendazole, zentel and pyrantel. The first two medications block glucose from the worm, the primary source of the worm’s energy. The third drug, pyrantel, paralyzes the worm so it can be easily removed (pooped) from the body.
“Since pinworm infections are highly contagious and there is a risk others can be infected, family members and anyone else in close contact should also be treated,” Dr. Olson said. “Additionally, because autoinfection (eggs being re-ingested) can occur after treatment, re-treatment is needed two weeks after the initial medication is given to ensure the worms and eggs have been killed.”
Take the following steps to help prevent spread and possible reinfection.
- Wash all bed linens, towels, and clothing daily with hot water (at least 104 degrees F/40 degrees C).
- Enforce personal hygiene. Wash hands with warm water and soap after using the bathroom and before and after eating.
- Trim your child’s fingernails and discourage them from scratching their tush and biting their nails.
- Avoid sharing toys, blankets and other items.
While you may want to bleach your house top to bottom, keep in mind that pinworms require very close contact with humans, so keeping a spotless house may not make a difference.
Will home remedies work at treating a pinworm infection?
There is no scientific evidence that home remedies, like raw garlic, raw carrots or coconut oil, can treat pinworms.
Are there any risks related to pinworm infections?
Pinworm infections usually don’t cause any serious issues. However, in rare cases, the following complications can occur:
Bacterial infection. A secondary infection can occur if your child scratches the area and causes the skin to break.
Urinary tract infections (UTIs). UTIs can develop if you don’t treat the pinworm infection.
Can I prevent a pinworm infection?
“The best way to prevent an infection is to encourage good handwashing,” Dr. Olson said. “This goes for the whole household.”
Wash your hands carefully with soap and warm water after using the bathroom, changing diapers and preparing and eating food.
Keep your child’s nails clipped short to avoid nail-biting and make sure they bathe daily. Change underwear and clothing daily as well.
Pinworms are a common intestinal infection that is highly contagious.
It won’t be pleasant if your little one gets infected (or reinfected!) with pinworms. Fortunately, the infection is typically mild, and there are effective medications available.
Don’t wait for the little monsters to spread. Instead, talk to your child’s health care provider immediately if your child shows signs and symptoms of infection.
Need help diagnosing or treating pinworms?
Schedule an appointment with a pediatrician near you.