The idea that your beloved child may be infested with worms is horrific to most parents but I am afraid to say it is a relatively common diagnosis. Thankfully it is also not usually serious and is easily treatable.

So what is it?

The “worms” are actually threadworms, which look like tiny “threads” between 2mm and 13mm long.  Threadworm infection is the most common “worm” infection worldwide and affects 50% of children in the UK at some time in their childhood.

What do I need to know in a nutshell?

  • The gut is infected by threadworms which lay their eggs around the anus which causes itching
  • It is treated with medication, which kills the worms but not the eggs so hygiene measures are also needed to prevent swallowing the eggs (touching bottom and touching mouth), which may cause a new infection.
  • Everyone living in the house needs to be treated even if they have no symptoms

How would my child catch threadworms?

To understand this you need to understand the lifecycle of the threadworm. They live in the gut for about 6 weeks and before they die they lay tiny eggs around the anus. The eggs are too small to see. When the child scratches their bottom the eggs get onto the fingers and under the nails and can then be swallowed if the fingers are put in the mouth. BUT, the eggs are tough and can survive for up to two weeks outside the body, on clothing, sheets and even in the air as dust, which can settle anywhere in the house eg toothbrushes. Any egg that is swallowed can hatch into worms and so the cycle continues.

It is easy now to see why it is so easy to catch the infection and why hygiene measures are so important. Threadworms are only spread from human to human, not through animals.

What age children are most at risk?

Anybody can catch threadworms but young children are most susceptible, as they tend to touch their bottoms more. They are also less good at general hygiene measures and they spend a lot of time with other children doing the same. The younger the child and the more basic their hygiene skills, the more likely they are to get it. However, once someone in the house has it, it is highly likely that everyone else in the house will get it

How can I tell if my child has threadworms?

The most common symptom is an itchy bottom, which may become sore from itching.  The itching sometimes wakes children at night. Some children experience mild tummy pain and loss of appetite.  In little girls the worms can migrate around to the vagina and urethra so rarely symptoms like vaginal discharge or problems urinating can occur.

Sometimes it is possible to see the worms in the faeces (poo) and occasionally you can see them if you look at the child’s bottom. The best way to do this is when the child as asleep. Using a torch, gently part the buttocks and you will probably see a few worms coming out of the anus. Don’t panic!  They have probably been there a while and you can get treatment in the next day or so. The other thing you can do is to try to collect some eggs to give to your doctor to send to the lab as a way to diagnose the infection. You do this by pressing a piece of sticky tape onto the anus for a few seconds, removing it and putting it into a container to be sent off. In the laboratory they can look under a microscope to detect any eggs that may be on the tape.

How do I get rid of them?

Medication AND hygiene measures

Medication – Mebendazole is the drug used to kill the worms and usually only a single dose is needed, with occasionally a second dose after 2 weeks if it is though re-infection has occurred. The most important thing is that EVERYONE in the household is treated. Children under 6 months, pregnant women in their first trimester and breastfeeding mothers should not use the medication. Instead the treatment is 6 weeks of the hygiene measure described below which would also clear the infection.

Hygiene measures are as important as medication in clearing the infection and are much more difficult and time consuming. However, if they are not done, re-infection will occur.  The aim is to clear the home and the body of any remaining eggs

You need to:

  • Wash all linen, nightwear, cuddly toys, towels etc on hot wash
  • Hoover and damp dust the home, including the bathroom, really well and discard the cleaning cloths

Then for 2 weeks, everyone in the house needs to:

  • Wash nightwear every day
  • First thing in the morning have a bath or wash well around the bottom, to get rid of any eggs laid overnight.  Also wash hands and scrub under nails
  • At night, wear close fitting underwear to prevent eggs getting onto the hands if there is itching at night.

To try to prevent infection again remember to wash hands well after going to the loo or changing nappies, including scrubbing nails. Try to avoid sharing towels and discourage children from sucking their thumb or biting nails. As airborne worm eggs can settle on toothbrushes, keep them in a cupboard and rinse well before use.

Unfortunately, threadworm infection along with head lice and occasionally roundworm infection (if you have dogs) are common childhood infestations that most parents will have to deal with at some point. Oh the joys of parenthood!

By Dr Chiara Hunt

Dr Chiara Hunt is a General Practitioner at the Sloane Street Surgery in London.  A mother of two, she is co-founder of The Bump Class, London’s go-to antenatal class for discerning mothers-to-be who want impartial, practical and sensible advice before the birth of their baby.