What is it?

Threadworms are quite common in children, although they can affect people of all ages.

While threadworms are unpleasant they are not a sign of uncleanliness. They can be effectively treated with medication and prevented by taking simple hygiene precautions both at home and in the centre environment.

Threadworms look like short pieces of white cotton and are usually between 5 - 10mm long. When threadworm eggs are swallowed they hatch in the gut where they live for several weeks. The female adult worm usually lays eggs at night which causes the bottom (anus) to itch.

The signs of threadworm include:

  • Itchy bottom, particularly at night.
  • Restlessness, bedwetting and irritability.
  • Threadworms on the outside of poos (faeces) or around the bottom (anus).
  • Decreased appetite.
  • Sometimes there may be no signs.

How does it spread?

When the bottom (anus) is scratched eggs can stick to fingers or under the fingernails and can then be easily transferred to the mouth, to food or to other people.

Exclusion period

Children are not required to stay away from the centre unless they are unable to comfortably take part in activities or are unwell.

Responsibilities of staff

  • Make sure all teachers, children and babies wash and dry their hands thoroughly after nappy change, toileting and before eating or handling food and infant formula bottles. Especially after attending to a child with threadworms.
  • Make sure that children wash their hands after nappy change if they are able to, and help children who cannot wash their hands properly.
  • Wash dress-up clothes in hot water and where possible wash toys in a dishwasher.
  • Remove play-dough, art and water-play until there are no more cases of threadworm.
  • Discourage the sharing of food and drink.

Responsibilities of parents

  • Children should wear underwear to bed during treatment to prevent scratching and eggs being picked up on fingers and under fingernails.
  • Make sure all family members are washing and drying hands properly after using the toilet, before preparing and eating food.
  • Wash hands thoroughly after attending to your child with threadworms.
  • Keep children’s fingernails short and discourage nail biting and thumb sucking.
  • Undress children in the shower, as this will make it easier to wash eggs away.
  • Shower children every morning and night to get rid of any eggs laid overnight.
  • Wash all bed linen, sleepwear, underwear and towels.
  • Vacuum furniture and carpets, and clean all toilets and bathrooms thoroughly.



  • Ask your family doctor or pharmacist for advice on the appropriate medication to use for treatment.
  • Follow the instructions on the medication.
  • All members of the family should be treated with this medication at the same time.

Hygiene measures (as stated above) and good handwashing are essential at both home and in the centre. Although medication will kill the threadworms in the gut, it will not kill the eggs which have been laid around the bottom (anus). The eggs can survive for up to two weeks outside of the body on underwear, bedding and in dust.


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Last updated 14 July 2022.