Pinworms (Enterobius vermicularis)
What is it?
Pinworms (Enterobius vermicularis) are small intestinal worms (less than ½ inch long). They live in the large intestine of humans. This is the most common worm infection in the U.S., especially in school-age children.
How is it spread?
Pinworms spread mainly through the fecal-oral route (microscopic eggs are accidentally swallowed). Eggs can live 2–3 weeks on indoor surfaces
Common ways infection spreads:
- Touching contaminated hands, surfaces, food, or objects
- Not washing hands after handling pajamas, underwear, bedding
- Scratching the itchy area → eggs get under fingernails → spread to surfaces or mouth
When is it contagious?
Pinworms are contagious as long as eggs are present, especially at night, when worms lay eggs around the anus. Anytime eggs are transferred to hands, clothing, or surfaces. Because eggs survive on objects for weeks, spread can happen easily and continuously if hygiene is not controlled.
Should the child stay home?
No exclusion is required. Children can return to school once treatment has started and good hygiene measures are in place.
How can we limit the spread?
- Key prevention steps:
- Wash hands thoroughly and often (especially after toilet use and before eating)
- Wash bedding and clothing in hot water
- Keep fingernails trimmed short
- Avoid scratching the affected area
- Shower in the morning to remove eggs laid overnight
Is there Treatment?
Wash hands thoroughly and often (especially after toilet use and before eating). Wash bedding and clothing in hot water. Keep fingernails trimmed short
Avoid scratching the affected area. Shower in the morning to remove eggs laid overnight.