CausesBy Mayo Clinic staff
A pinworm infection occurs when you accidentally swallow pinworm eggs. The microscopic eggs can be carried to your mouth by contaminated food, drink or your fingers. Once swallowed, the eggs hatch in the intestines and mature into adult worms within a few weeks.
Female pinworms crawl to the anal area to lay their eggs, which often results in anal itching. When you scratch the itchy area, the eggs cling to your fingers and get under the fingernails. The eggs then get transferred to other surfaces, such as toys or bedclothes. The eggs can also be transferred from contaminated fingers to food, liquids, bed linens, clothes or other people.
Pinworm eggs can survive for two to three weeks on surfaces. You can become infected with pinworms if you consume contaminated food or drink or if you touch a contaminated surface and then touch your mouth.
- Parasites and health: Enterobiasis. Centers for Disease Control and Prevention. http://www.dpd.cdc.gov/DPDx/html/Enterobiasis.htm. Accessed Feb. 16, 2012.
- Kliegman RM, et al. Nelson Textbook of Pediatrics. 19th ed. Philadelphia, Pa.: Saunders Elsevier; 2011. http://www.mdconsult.com/das/book/body/208746819-6/0/1608/0.html. Accessed Feb. 16, 2012.
- Fact sheet: Pinworm infection. Centers for Disease Control and Prevention. http://www.cdc.gov/parasites/pinworm/index.html. Accessed Feb. 16, 2012.
- Ferri's Clinical Advisor 2012. 5 Books in 1. Philadelphia, Pa.: Mosby Elsevier; 2012. http://www.mdconsult.com/books/about.do?about=true&eid=4-u1.0-B978-0-323-05611-3..C2009-0-38601-8--TOP&isbn=978-0-323-05611-3&uniqId=291436269-101. Accessed Feb. 16, 2012.
- Pinworm infection. National Institute of Allergy and Infectious Diseases. http://www.niaid.nih.gov/topics/pinworm/Pages/default.aspx. Accessed Feb. 16, 2012.
- Gardner AS. Vulvovaginitis and other common childhood gynaecological conditions. Archives of Disease in Childhood: Education and Practice Edition. 2011;96:73.
- Stermer E, et al. Pruritus ani: An approach to an itching condition. Journal of Pediatric Gastroenterology and Nutrition. 2009;48:513.