Pinworm Childhood Illness Symptoms

Naked boy (2-4) scratching buttocks, rear view
Pinworm. Gage / Getty Images

Like scabies and head lice, pinworms are one of those things that parents dread hearing about since they associate them with poor hygiene.

Pinworms, which also go by the scientific name Enterobius vermicularis, very commonly cause infections in kids, though, especially those in day care.


Pinworms are spread from child to child after they ingest microscopic pinworm eggs.

How do kids get exposed to pinworm eggs?

Like most other infections, they get them from other kids.

A child with a pinworm infection will classically get the eggs on his fingers, as he scratches his bottom, and can then pass them on to other children.

It may sound gross, but after ingesting the eggs, they hatch and develop into adult pinworms in the child's small and large intestine. Mature adult pinworms mostly live in the child's colon, coming out of their rectum to lay more eggs, which leads to the symptoms of pinworms.

Symptoms of Pinworms

Since adult pinworms are so small (they look like 1/2 inch long white threads) and only come out at night, they can be very hard to see. That can make the diagnosis of a pinworm infection difficult.

Still, even if you don't actually see the pinworms, you might suspect pinworms if your child has:

  • rectal itching, which may be worse in the middle of the night
  • restless sleep
  • secondary nocturnal enuresis (wetting the bed again at night after a period of staying dry)

Since younger children often have sleep problems and may have rectal itching because of not wiping well after having a bowel movement, in addition to looking for the symptoms of pinworms, a formal diagnosis can be a good idea. This can be done by looking for the adult pinworms in the middle of the night or asking your pediatrician about doing a "tape" test or pinworm prep.

These tests can help your pediatrician to identify the pinworm eggs under a microscope.

The "tape" test involves placing a small piece of scotch tape on the skin around your child's rectum first thing in the morning before he takes a bath. You can then bring it to your pediatrician, who will press the tape onto a glass slide and examine it under a microscope slide to look for pinworm eggs. Your pediatrician will often provide a pinworm prep kit to make this process easier.


Kliegman: Nelson Textbook of Pediatrics, 18th ed.

Long: Principles and Practice of Pediatric Infectious Diseases, 3rd ed.