Threadworms

Threadworms are parasites that live inside the gut (large intestine) of humans. People can get infected by several different worms, but threadworms (pinworms) are the most common. Children often get threadworms, and they can easily pass them on to adults.

Symptoms

Threadworms look like long, thin, tiny pieces of white thread. Sometimes there may be no symptoms of infection, but some common signs of threadworm infection are:

• itchy bottom (also vagina in females), especially noticeable at night time
• children may be irritable, unhappy or restless
• loss of appetite
• not sleeping well (some children may wet the bed at night).

When a child complains of an itchy bottom:

• Use a torch at night to check the anal area, particularly an hour after the child has fallen asleep. Look for white, thread-like worms around the anus.
• Look for white, thread-like wriggling worms that may be moving about in bowel motions.
• Briefly apply sticky tape around the anus in the morning (before bathing) and check for any attached threadworms.

Causes

Animals get many worms (such as hookworms) which they can spread to humans, but they cannot infect people with threadworms. You can catch threadworms from other infected people.

When the eggs are transferred into the intestine (gut), they hatch. After about two weeks they become full grown adult worms. Female threadworms then move down the gut and lay their eggs outside near the bottom area (anus), usually at night time when the person is sleeping. The eggs are attached to the skin with a sticky glue-like substance which irritates the skin, making it itchy.

When the bottom is scratched, the eggs get stuck under the fingernails and can then easily be transferred to items such as toys, clothes or utensils. Children also often put their fingers into their mouths, and so can easily ingest the eggs, which when swallowed, start the life cycle again. Threadworm eggs can survive up to two weeks outside of the body.

Lifestyle options

Threadworms have to be treated with medicines, and everyone in the house must be treated, but there are some important ways to prevent the spread of threadworms if there is an infection:

• Encourage your child not to scratch their bottom. If they feel really itchy, they could scratch over their underpants, so they don’t directly touch or scratch the skin. Tight underpants can make it difficult to scratch bare skin.
• Discourage nail biting or finger sucking. Keep fingernails clean (scrub with a soft brush) and trim short.
• Ensure children wash their hands and fingernails well with soap after each visit to the toilet and before eating food.
• Wash clothes (including underwear, bedding and toys) in hot water to kill the eggs. Do this for a few days when you start treatment to prevent any surviving eggs hatching.
• Change your children’s clothes in the shower area and avoid shaking their clothes, as this will spread the eggs.
• Don’t share clothes or towels.
• Shower the child on the night of the treatment, then again in the morning to wash away eggs that have been laid during the night.

Pharmacy options

Always inform pharmacy staff if you are taking any other medicines, or if you have any other health conditions, because some over-the-counter medicines may not be suitable for you.

Medicines used to kill threadworms do not kill the threadworm eggs, so a repeat dose may be required. Check the pack instructions, or ask the pharmacist for the right dose for children under 2 year of age and for pregnant and breastfeeding women. Children can go to school as soon as they are treated.

Everyone in the house should be treated with threadworm medicines, even if they do not show signs of threadworms. Treat everyone in the family on the same day. Your pharmacist can advise if a second dose of medicines is needed in 2 weeks’ time.

Ask your pharmacist for advice on the most suitable treatment for you.

See a doctor if:

• you notice blood in the bowel motions, weight loss or stomach pain
• you or your family have recently returned from overseas – it may be a different type of worm
• signs of threadworm infection do not go away after a repeat treatment in 2 weeks’ time. Your doctor might recommend a prescription medicine.

More information

Health Direct: www.healthdirect.gov.au

MyDr: www.mydoctor.com.au

Disclaimer: The information provided is a guide only, is current at time of publishing, and is not intended to replace the advice of your pharmacist or doctor.

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