Intestinal worms - Oxyuriasis

July 2017

What do they look like?

Threadworms are small white worms, approximately 0.5 cm long. Threadworms are parasites and infect the human digestive systems. Anyone can get them but are more common in children. They are found in the rectum where the female worm migrates to the anus to lay eggs, usually at night.


They cause at itchy bottom (pruritus ani), particualry at night. This prevents the child from sleeping, making them tired and irritable. In girls they can migrate to the vagina where they their lay eggs, this causes irritation and itching in the perineum (vaginal area).

Because of the scratching, it can make the bottom sore and secondary infection can occur such as impetigo. Stomach pains and diarrhoea are sometimes noted.


Threadworms are easily passed on as the eggs can survive outside the body for 2 weeks. The eggs can settle on bedding, dust or other objects around the home. Children infected with threadworms pass the eggs on to other children when playing. They then swallow the eggs which hatch and quickly grow into adult worms. It is therefore crucial that hand hygiene and scrubbing under finger nails is important to prevent the spread of worms.


The diagnosis is carried out by visualising the worms (white filaments) in your childs stools. If threadworms are suspected but you can't find any worms in the stool, then check your childs bottom at night. Part their buttocks and shine a torch and the worms may appear as they lay their eggs outside the anus at night. Finally, press a piece of cellotape over the skin close to the anus and place it on a glass slide to be analysed in the laboratory. This needs to be done first thing in the morning, before wiping the bottom or taking a shower.


All family/household members need to be treated, even those without symptoms. Strict hygiene for everyone to prevent re-infection. An anti-parasitic treatment must be prescribed for all contacts. Two doses are given 2 weeks apart. Itching may continue to persist for about 7 days after the beginning of the treatment.

Objects and bedding within the home could be infected - so a spring clean is necessary to eradicate the eggs, which may have settling within the home. For example - damp dusting, washing bedding/clothing, hovering

Avoiding a recurrence

Some simple measures will avoid a recurrence.
  • Cleaning, vacuum-cleaning, airing...
  • Disinfecting the bed linen, clothing, toys.
  • Not to shake the bed linen in order to avoid the dissemination of eggs.
  • Washing hands regularly and more particularly before eating and after having been to the toilet
  • Keep fingernails short and do not bit them.


Vers dans les selles - oxyures - Symptômes et traitement
Vers dans les selles - oxyures - Symptômes et traitement
Lombrices intestinales (oxiuros)
Lombrices intestinales (oxiuros)
Latest update on November 12, 2013 at 04:19 AM by Jeff.
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