Pinworm infection

Pinworm infection is a common intestinal worm infection that mainly affects children. Typical symptoms include itching of the anal area, especially in the evening and night. Pinworm infections can spread easily. They’re most common in children between the ages of 5 and 10, people who live in institutions, and those who have regular, close contact with individuals in these groups. You can get rid of pinworms with medications and good hygiene. It is especially important to wash your hands carefully to prevent the spread of infection.


Children and sometimes adults become infected by ingesting pinworm eggs. 10-30 percent of all preschoolers get pinworm infection at some point, but even adults can suffer.


The pinworm’s eggs are found in dust, textiles and in the fur of pets. Animals cannot be infected themselves, but the eggs can be in their fur. The eggs are difficult to detect, but sometimes you can see white, millimeter-sized dots.


If the eggs of the pinworm enter the gastrointestinal tract they remain in your intestine until they hatch and then mature. They exit through the anus at night to lay new eggs. Sometimes the worms can be found in stools. You can see them with the naked eye – they are yellowish-white, thin and 5-13 mm long.


Pinworm infection is spread through the eggs of the worm that sticks to fingers, toys, textiles or the fur of animals. You get infected when you put contaminated things with the eggs in your mouth. The eggs develop for 3-4 weeks into adult worms in the gastrointestinal tract. Then they lay new eggs in the anal area.


Children with pinworm infection can infect themselves again if they scratch their anus and then put their fingers in the mouth.


Pinworm infection isn’t always clear to diagnose. You can be infected without experiencing any symptoms. You may feel strong itching of the anal area where the pinworm lays its eggs – usually worse at night, when the pinworm is most active. Children who get pinworms often have trouble sleeping and babies can show their discomfort by kicking their legs.


Common symptoms include:


  • itching and redness of the anal area
  • swelling of the anal area
  • small, yellowish-white worms in the anal area or in the stool
  • restless sleep
  • stomach pain, nausea and vomiting (rare)


Bear in mind that itching does not have to be caused by pinworm infection – there are other infections that produce similar symptoms, for example: eczema, candidiasis, anal fissures or hemorrhoids.

Prevention and protection

To prevent the spread of infection, it is important to practice good hygiene. Also, to ensure both worms and eggs are removed, bedding and underwear should be washed at 60 degrees, because the eggs can survive in colder temperatures.


To reduce the risk of infection:


  • wash your hands carefully and often with liquid soap
  • use a paper towel when drying
  • cut your nails short
  • sleep in pyjamas
  • change underwear and pajamas every day
  • change towels frequently, preferably every day
  • change and wash children’s clothes after school 
  • clean the toilet and sink every day
  • wash textiles and toys at 60 degrees
  • clean any surfaces that might be infected.


Please tell the staff at the school if your child has a pinworm infection so that both the staff and other parents can be alerted to any symptoms in other children.


Your doctor can usually treat a pinworm infection effectively with oral medication. Pinworms usually appear in anal area, but if you are unsure, a so-called tape test can help with the diagnosis.


Since pinworms pass so easily from one person to another, everyone living in the household of an infected person usually needs treatment at the same time to prevent reinfection. Caregivers and others who have close, personal contact with the individual should also receive treatment.


The most common and effective medications to treat pinworm infection are mebendazole or albendazole.


One course of medication usually involves an initial dose, followed by a second dose two to three weeks later. More than one course may be necessary to fully eliminate the pinworm eggs. Creams or ointments can soothe itching skin in the area around the anus.

When to consult a doctor

If your child has a pinworm infection and is under two years old or weighs less than 10 kilos, you should see a doctor immediately.
If you or your child has any symptoms that do not disappear despite treatment, you should consult a doctor.

How APPOTEK can help

APPOTEK can help you with pinworm infection. In the initial consultation, a nurse or a physician will make a diagnosis, then may prescribe medicine or refer you for further examination. If your child has the infection, they should also attend the consultation.


Valeria Chernikova, Neurologist, M.D.