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Threadworms: all your questions answered

Child washing hands at sink
It’s easy to feel horrified if your child gets threadworms, but don’t panic! They’re very common among kids – and easy to treat. Here are all your pressing questions answered.

What are threadworms?

These unwelcome visitors are small worm parasites that infect your intestines. “They’re called threadworms because they look like pieces of white cotton,” says GP Dr Wendy Snell of Cadogan Clinic. “They vary in size from about 2mm to over 1cm long.”

How do you catch them?

“You get threadworms by ingesting their eggs,” explains Dr Snell. “Female threadworms work their way through the intestine to the back passage where they come out and lay eggs on the bottom. These can become dislodged and fall onto bedding and can then get onto your hands. The eggs cause itching, so if you scratch the area they can get under your fingernails, too.” It’s also thought that the eggs can become airborne if they’re on bedding that is shaken and can be ingested that way.

Why are they so common in children?

Children are more prone to rolling around on the floor, putting things in their mouths, and being lax about washing their hands. Kids can also swallow eggs by playing with children who have eggs on their fingers or playing with toys which have been contaminated with eggs. Their lack of adult self-restraint means they’re also more prone to scratching an itchy bottom!

What are the risks?


“The females come out to lay their eggs at night and this can cause itching, which can interrupt sleep and cause irritability,” says Dr Snell. “They can cause tummy pains and disturbances of the bowel but this is only really an issue if they’re left untreated.”

How do I know if my child has threadworms?

The common symptoms are itching, tiredness and irritability. “You may be able to see the worms when your child has a poo,” explains Dr Snell. “You can also use a torch and have a look at their bottom when they’re asleep to see if you can spot them.” It sounds horrible – but remember they’re only tiny!

How are they treated?

You can buy an over the counter treatment and it’s recommended that the whole family take it. The high risk of transmission means other family members might well be infected even if they’re not showing any symptoms. Speak to your pharmacist if you’re pregnant, breastfeeding or planning to treat a young baby to ensure the treatment you buy is safe. It’s also important to wash any bedding and towels to get rid of any eggs, as they can live for up to two weeks outside the body. “Worms like sugar,” says Dr Snell, “so it can also be a good idea to cut back on sugar in your child’s diet, too.”

How can we avoid re-infection?

“The main thing to do is to stress the importance of good hygiene to your children,” says Dr Snell. “Teach them to wash their hands after going to the toilet and before meals and to scrub under their fingernails. It’s also a good idea to keep fingernails short.” But try not to get too worried about threadworms. “They’re very common and no matter how vigilant you are they can be hard to avoid. So don’t panic – or feel embarrassed – if your child gets them.”

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