Threadworm (Pinworm)

Understand threadworm, and its causes and symptoms.

Threadworm (Pinworm)


What is threadworm?

Threadworm, also known as pinworm, is when tiny worms (Enterobius vermicularis) infect your poo via the intestines, colon or rectum. It is a particularly common condition among children, but it can affect people of all ages.


Threadworm infection can be caused by swallowing or breathing in threadworm eggs. Pinworm eggs are highly contagious and can survive for 2 to 3 weeks on surfaces, so it is relatively easy to pick them up on bathroom fixtures, food, liquids, bedding, clothes or other people via contaminated fingers.


Sometimes threadworm causes no symptoms at all, but the most common symptoms of a threadworm infection include:

  • Intense anal itching around the anus, especially at night which can disrupt sleep
  • Visible, thin and white worms (6 to 13 millimetres) around the anus or in the stool
  • Irritation and redness of the affected area

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