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- Intestinal infection with Enterobius vermicularis
- Characterized by perineal and perianal itching
- Usually worse at night
- System(s) affected: gastrointestinal; skin/exocrine
- Synonym(s): enterobiasis
Predominant age: 5 to 14 yearsPrevalence
- Most common helminthic infection in the United States
- 20 to 42 million people harbor the parasite.
- ~30% of children are infected worldwide.
More common in children, who are more likely to become reinfected
Etiology and Pathophysiology
- Small white worms (2 to 13 mm) inhabit the cecum, appendix, and adjacent portions of the ascending colon following ingestion.
- Female worms migrate to the perineal areas at night to deposit eggs; this causes local irritation and itching.
- Scratching leads to autoingestion of the eggs and continuation of pinworm’s life cycle within the host. Eggs incubate 1 to 2 months in the host small intestine. When mature, female pinworms migrate to the colon where they lay eggs around the anus at night, and the lifecycle continues.
- Infestation by the intestinal nematode E. vermicularis
- Crowded living conditions
- Poor hygiene
- Warm climate
- Handling of infected children’s clothing or bedding
- Hand hygiene, especially after bowel movements
- Clip and maintain short fingernails.
- Wash anus and genitals at least once a day, preferably during shower.
- Avoid scratching anus and putting fingers near nose (pinworm eggs can also be inhaled) or mouth.
Commonly Associated Conditions