Threadworms – symptoms, treatments and prevention

If your child starts scratching, especially at night, they may have threadworms

What are threadworms?

Threadworms are small worm parasites that infect the intestines. They are white and look like a small piece of thread. Adult worms live up to six weeks and one female threadworm can release thousands of eggs, too small to be seen by the naked eye.

Female threadworms lay their tiny eggs around the anus or vagina. They’re spread when the infected person scratches the area, as the eggs will transfer onto their fingers and when they touch another part of their body or another surface, they transfer the eggs. Someone else then may touch that surface and their mouth and become infected.

If your child comes into contact with someone who has threadworms then they may become infected through sharing pencils and toys or by touching the same surfaces. Threadworm eggs can survive on surfaces for up to three weeks.

What are the symptoms?

Threadworms sometimes have no symptoms but if your child has the infection they may complain of itching around the anus or vagina, especially at nighttime when the female threadworms lay their eggs. This itching may cause your child to have a disturbed sleep so they may be irritable in the morning.

If your child has a severe infection, they could lose their appetite and in turn lose weight.

You may be able to spot if your child has threadworms even if they haven’t complained of any itching. The best time to try and see the threadworms is at night, two or three hours after your child has fallen asleep as the worms may be visible on your child’s underwear, pyjamas or bed sheets.

You might also see threadworms in your child’s faeces. 

Are threadworms common?

Yes, especially in young children who aren’t aware of the importance of washing their hands regularly. Up to 40% of children under 10 in the UK may be infected with threadworms, according to the NHS.

Threadworms are common in crowded conditions, such as school, because there are more people to spread the infection by direct and indirect contact. It’s especially common in schools because children share toys and hold hands every day, making re-infection easy. 

Only humans are affected by threadworms and children can’t catch the infection from animals.

Do you need to take your child to the doctor?

Yes. If your child is diagnosed with threadworms, then the whole household must be treated, even if you think you or other family members don’t have them.

The medication your doctor may prescribe is mebendazole, which is available as a chewable tablet or liquid. Mebendazole may also be bought over-the-counter, but make sure you follow the instructions carefully.

The only way to get rid of threadworms entirely is by following a strict good hygiene method for up to six weeks as medicine will only kill the worms and not any eggs that may have been laid.