Pinworms are small, threadlike parasites that live in the colon and rectum of infected individuals. Pinworms are a species of roundworm (nematode) called Enterobius vermicularis. The worms are just a few millimeters long. Pinworm infections are the most common worm infection in the U.S. Pinworm infection occurs most often in children, people in institutions, and those who live in a household where people have pinworms. Pinworms in kids may spread throughout child care centers.
Pinworm infection symptoms usually range from mild to nonexistent. Adult female pinworms travel outside the body at night and lay eggs around the anus. Pinworms in the anus may cause itching and discomfort. Signs of pinworms in kids may include irritability and sleep problems. Some people do not have any pinworm symptoms. They are small, but sometimes people can see pinworms in stool.
Anyone can get pinworms, but the infection is most common in school-aged children. The infection often spreads to others in daycare, school, home, and other similar settings. Pinworm infection can be distressing but it is very common. It is estimated that more than 30% of children worldwide harbor pinworms. Pinworms in babies and pinworms in toddlers may occur as well. What do pinworms look like? They are small, white, thread-like worms that are about ¼ inch to ½ inch long.
Pinworms in children are a common occurrence, but pinworms in adults happen, too. Parents may get pinworms from their infected children. Adults who work at daycare centers, schools, or with institutionalized people may become infected. The parasites are small, but you may be able to see pinworms in stool.
How do you get pinworms? Pinworm infection is spread through a fecal-oral route of transmission. This refers to infectious agents in the GI tract passing from one person to another via contaminated objects and lack of proper hygiene (hand washing after using the restroom). Where does pinworm come from? People are newly infected by ingesting pinworm eggs that may be on countertops, shared food, bedding, clothing, and other objects. Children may ingest pinworm eggs by sucking on their fingers or thumbs. Pinworm eggs may also become airborne, inhaled, and swallowed, resulting in infection.
People may worry about pinworms in dogs and pinworms in cats, but it is a common misconception that family pets harbor the parasites. While pet dogs and cats can harbor many other types of parasites that can infect people, humans are the only host for pinworms.
Pinworm eggs hatch to release larvae which then grow into adult worms. Adult female pinworms lay eggs on the skin around the anus. After a host ingests the eggs, larvae hatch when they reach the small intestine. The larvae mature into adult pinworms which then travel to the colon. Adult pinworms live about 2 months. Sometimes pinworm eggs may become airborne and inhaled and swallowed, although this is rare.
Pinworms can be diagnosed based on symptoms and sometimes people can see pinworms in poop. In other cases, a pinworm tape test may be done to collect and identify pinworm eggs under a microscope. The tape test for pinworms involves wrapping a piece of cellophane tape, sticky side up, around a clean tongue depressor. The tape is then pressed on the skin around the anus as soon as the person with suspected worms wakes up. Do not bathe, use the restroom, or change clothing before doing the tape test so as to not disturb potential pinworm eggs. If possible, it is a good idea to obtain samples 3 days in a row to maximize the chance of identifying any eggs that are present.
Pinworm treatment may involve prescription and over-the-counter medications. Mebendazole and albendazole are prescription medications for the treatment of pinworms, and pyrantel pamoate is an over the counter pinworm medicine. One brand of pyrantel pamoate available in many pharmacies is called Reese's Pinworm Medicine. The medications only kill adult pinworms so they must be given in two doses. The first dose kills existing adult pinworms, and the subsequent dose given 2 weeks later kills any new adults that have hatched from any remaining eggs. If multiple family members or children in a daycare or school setting are infected, it is best to treat everyone at the same time to minimize the chance of reinfection.
The best way to avoid getting pinworms is to practice rigorous good hygiene. Wash hands well using soap and warm water after using the restroom. Wash bedding, towels, and undergarments in hot water. Always wash hands before eating. Sanitize hard surfaces. Showering is preferred over bathing. Teach children about the importance of hand washing and dissuade them from biting their nails. Pinworm eggs may survive on surfaces for up to 2 to 3 weeks.
Medications used to treat pinworm infection, such as pyrantel pamoate, have not been studied in pregnant women. It is not known whether these medications are safe to use in pregnancy. If a pregnant women is losing excessive amounts of weight or not sleeping due to pinworm infection, a doctor may treat her when she has reached the third trimester. It is believed that any potential risk to the developing baby from the use of pinworm medication may be reduced at this time. Doctors may treat women for pinworm infection if the benefits outweigh the potential risks of using the medications. It is not known whether pyrantel pamoate is transferred to the baby in breast milk.
Many people wonder if there are effective home remedies for pinworms. Although medication is the most effective pinworm treatment option, several foods and herbs have antiparasitic properties. Garlic, coconut, coconut oil, pumpkin seeds, and grated carrots may have antiparasitic activity. So do grapefruit seed extract and wormwood extract. Always check with your doctor before using home remedies for pinworms or any other condition.
As long as pinworm infection is diagnosed and treated, the potential for complications is low. Severe pinworm infections may lead to vomiting and weight loss. If someone who has pinworms scratches excessively, this may lead to secondary bacterial infections. Rarely, females may suffer from pinworms in the vagina. Pinworm infection may lead to appendicitis or fallopian tube inflammation.
Pinworm infection is common and straightforward, but there are some surprising facts about the parasitic illness.
- Female pinworms are about 10-13 millimeters in length (about ½ inch) while males are just 4 to 5 millimeters long (about ⅓ inch).
- Female pinworms die after laying eggs.
- Pinworm eggs are so small they may become airborne and inhaled, even on dust particles.
- About 10% of the general population in the U.S. suffers from pinworm infection at any given time.
Do you or your child have pinworms or is it something else? There are several types of worms that can make people sick. Roundworms or ascariasis are worms that cause coughing, wheezing, fever, abdominal cramps, and even intestinal obstruction. Roundworm eggs are found in soil where they can remain for years. Hookworms live in contaminated soil and we contract them if we step on them. They attach themselves to the small intestine where they suck blood. Symptoms of hookworm infection include abdominal pain and anemia. See your doctor right away if you develop concerning symptoms so you can be diagnosed and treated.
IMAGES PROVIDED BY:
- Getty Images
- Getty Images
- Getty Images
- "Enterobius vermicularis life cycle" by SuSanA Secretariat / MedicineNet / Bigstock
- iStock / Getty Images
- U.S. Agricultural Research Service
- ABCs of Bumps & Bruises, a Guide to Home & Herbal Remedies for Children: "Worms."
- American Family Physician: "Common Intestinal Parasites."
- Centers for Disease Control and Prevention: "Parasites – Enterobiasis (also known as pinworm infection)."
- National Organization for Rare Diseases: "Enterobiasis."