Types of Worms – Threadworm

There are many different types of worms that can cause an infection in humans, with one of the most common types in New Zealand being threadworms (sometimes called "pinworms"). These long, thin worms draw their name from their appearance. They look a little like pieces of cotton thread, and adult females can grow up to 1.5cm in length.

Threadworms are a fact of life for many young children getting to know the world around them – and the more you know about the various different types of worms, the more prepared you can be in the case of infection among little ones or other members of the family. Here's our comprehensive factsheet about this type of worm, the symptoms they cause, and how to get rid of them.

A threadworm overview

Threadworm or pinworm, are tiny white worms which can infect the intestines of humans. They're a common worm parasite among young children, particularly those under the age of 10. The worms themselves have a blunt head, a pointed tail, and can live for up to six weeks inside the human body1.

How do you get threadworms?

Catching worms does not mean a person is 'dirty'. The tricky blighters are highly contagious – they can be caught in two main ways: directly, or indirectly. Catching them directly involves physical contact with an infected person. Your child might directly catch worms while playing a contact sport with friends or holding hands with a pal in the playground at school. Catching them indirectly can be the result of, for example, touching a door handle, a washbasin tap or a piece of furniture that has previously been touched by someone who’s infected. These worms are especially common in children, and infections are often clustered in families, day-care centres and schools. It is a human-specific parasite and cannot be contracted from pets.

How can I tell if my child has a threadworm infection?

Infections can be the cause of slight changes in your child's behaviour which can be discovered by attentive observance. If your child has experienced an itchy bottom, trouble with sleeping, irritability or any loss of appetite, there's a chance they might have an infection.

The most common symptoms of an infection can include:

  • An itchy bottom
  • General irritability
  • Trouble sleeping, or restless sleep
  • Sudden lack of appetite2

For definitive proof of infection, one of the most common ways is to look for worms on the outside surface of bowel motions (these resemble fine pieces of cotton thread, up to 1.5cm long) Also look for moving worms or eggs around the anus about an hour after the child has gone to bed. Using a torch, worms should be visible to the naked eye. These eggs resemble tiny white specks which are laid by the female worm.

Another useful way of detecting eggs is to try out the 'sticky tape test' – gently press a small piece of sticky tape to the anus and remove. If there are eggs present, they'll show up as white specks on the tape when held up to the light.

There's also a chance that your child may not show any symptoms of a worm infection, as worms can be asymptomatic. Adults in particular may actually show no signs of infection – that's why it's crucial to have treatment on hand and treat the whole family once one member starts to exhibit symptoms of an infection.

In some rare cases among girls, the female threadworms migrate from the anus to the vagina, which can lead to very uncomfortable vulvovaginitis – inflammation of the vaginal area. The symptoms of this include irritation and vaginal discharge, which are both highly unpleasant. It will not survive for long in this region, but if you suspect vulvovaginitis, seek medical attention and treat the worms with a product like COMBANTRIN® as soon as you can.

But my children are always squeaky clean! How could they have caught threadworms?

While it's true that poor hygiene can contribute to the spread of threadworm, cleanliness and hygiene actually has no bearing on the likelihood of a child catching it. They are simply highly contagious, and a natural part of growing up for many – it's through no fault of the parents.

Infections are spread easily among children because of their tendency to come into frequent physical contact with others, whether they're engaging in team sport, going camping with friends or playing 'tag' with their brothers and sisters. It doesn't matter how many times they wash their hands after playing or coming home from school – they are passed during those unique sharing moments that children have with one another at school, on holiday, at sports and in a multitude of other circumstances. Threadworms can be caught from harmless actions like opening a door or touching a table that has been touched by someone with an infection.

Treat Worm Infections in Children

Treat Worm Infections in Children

Threadworm infections can happen to anybody. Be prepared, to stay on top of worms.

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