A child who is restless at night and keeps scratching around the bottom... Pinworms, also called threadworms, are the most common intestinal parasite in pre-school and school-age children. The medical name of this parasite is Enterobius vermicularis: a white, thread-like worm a few millimetres long. It spreads through close contact, not dirt, and is common in clean, well-cared-for families too. The good news is that it is easy to diagnose and, when managed correctly, does not cause a serious health problem.

How do pinworms live and spread?

Female worms leave the bowel at night and lay eggs on the skin around the anus. Within a few hours these eggs become infectious. As the child scratches, eggs settle on the fingers and under the nails, and from there they:

  • are swallowed again via hands put in the mouth,
  • pass onto toys, door handles, food and bedding,
  • reach siblings and adults living in the same home.

According to the US Centers for Disease Control and Prevention (CDC), the eggs can survive on surfaces for up to 2-3 weeks. Unless the scratch-and-swallow cycle is broken, the infection keeps feeding itself. In children who bite their nails or suck their thumbs, this cycle continues more easily.

Pinworm symptoms

  • Itching around the bottom that gets worse at night — the most typical symptom
  • Difficulty falling asleep, frequent waking, restlessness and irritability during the day
  • Itching and irritation of the genital area in girls
  • Redness and scratch marks from scratching; sometimes a secondary skin infection
  • White, thread-like worms seen in the stool or around the bottom at night

Some children have no symptoms at all. Pinworms are a rare cause of tummy pain; if the pain is marked or persistent, other causes should be looked for (see abdominal pain in children). The UK National Health Service (NHS) lists bed-wetting among the less common symptoms; even so, newly started bed-wetting should be assessed separately for other causes.

How is it diagnosed?

Because the eggs are laid around the anus rather than inside the bowel, they are often missed in a stool test. The most widely used method is therefore the tape test: in the morning, as soon as the child wakes and before using the toilet or washing, a piece of clear tape is pressed onto the skin around the anus, lifted off and examined under a microscope. A single test may miss the eggs; the doctor may ask for it to be repeated on several mornings. Worms can also be seen directly by shining a torch around the bottom 2-3 hours after the child falls asleep.

Treatment: why the whole family?

Once the diagnosis is made, treatment is planned by the doctor. The general approach in international guidelines is:

  • Everyone living in the same home is treated at the same time — including those without symptoms. Otherwise the parasite keeps circulating in the family.
  • Because worm medicines do not kill the eggs, treatment is usually repeated after two weeks.
  • Medicine choice differs for children under two, in pregnancy and during breastfeeding; in these groups medicine is only used on a doctor's advice.

There is no reliable evidence that home remedies such as garlic or pumpkin seeds cure pinworms.

Hygiene measures that prevent reinfection

The NHS recommends continuing these measures for at least 2 weeks alongside medicine, or for 6 weeks if medicine cannot be used:

  1. Washing hands with soap and water after the toilet, after nappy changes and before eating, and scrubbing under the nails
  2. Keeping nails short; reducing nail-biting and thumb-sucking
  3. Wearing underwear at night and changing it in the morning; showering every morning
  4. Washing pyjamas, sheets, towels and soft toys on a hot cycle; not shaking out bedding
  5. Not sharing towels or face cloths
  6. Cleaning bathroom and kitchen surfaces with hot water and dusting with a damp cloth

When should you see a doctor?

Children with bottom itching and broken sleep, those whose complaints continue despite treatment, whose scratch wounds become infected, or girls who develop a genital discharge should be examined. If weight gain has stalled, growth is also checked as part of well-child check-ups. If your child has symptoms, you can book an appointment at Özel Düztepe Yaşam Hospital in Şahinbey.