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It is possible that the main title of the report Enterobiasis is not the name you expected. Please check the synonyms listing to find the alternate name(s) and disorder subdivision(s) covered by this report.


  • Oxyuriasis
  • Pinworm Infection
  • Seatworm Infection

Disorder Subdivisions

  • None

General Discussion

Enterobiasis or pinworm infection is a common, contagious, parasitic infestation found mainly in children. The disorder is spread by swallowing or inhaling the tiny eggs of the pinworm. Enterobiasis rarely causes any serious physical problems except for the main symptom, which is severe rectal itching.


The major symptom of enterobiasis is itching in the anal area. There may also be restlessness and difficulty sleeping. Secondary bacterial infections may develop in the areas that are constantly scratched and, very infrequently, the vagina may become involved in young girls. Very rarely, enterobiasis may lead to appendicitis or inflammation of the fallopian tubes in females.

Many children with enterobiasis show no symptoms (asymptomatic). In rare cases, nausea, loss of appetite, vomiting, involuntary discharge of urine at night (enuresis) or stomach pain may occur. The disorder is usually first identified when live, thin, white pinworms, (females are about 10 mm in length and males are 4-5 mm in length) are noticed in the feces.


Enterobiasis is contracted by ingesting the eggs of pinworms, which may be carried on fingernails, clothing, toys or bedding. The eggs may also be inhaled in dust. The infection may be transmitted to others by hand-to-mouth contact with contaminated food or objects.

The female worm, residing in the rectum, usually crawls out through the anus at night and deposits her eggs in the surrounding (perianal) area. The sticky, gelatinous substance in which the eggs are deposited and the movements of the female worm usually cause intense rectal itching. The adult female worm dies after laying the eggs. However, the eggs may survive for as long as three weeks. As the child scratches the area, the tiny eggs become imbedded under the fingernails. These eggs may be swallowed, continuing the parasites' lifecycle. The parasites reach maturity in the large intestine within two to six weeks.

Affected Populations

Enterobiasis is a common disorder affecting both sexes in equal numbers. It most frequently occurs in children during nursery school or kindergarten years. An entire classroom of children may be affected very quickly as the infection is spread from one child to the next.

In the United States, it is thought that about 10% of the general population is infested but that the number is declining.

Standard Therapies

Enterobiasis usually is self-limiting if good hygiene is followed. However, most individuals prefer some type of treatment, and the drug pyrantel pamoate is usually prescribed. One dose of pyrantel pamoate, repeated in two weeks, usually stops the infestation. Reinfestation is likely since eggs deposited as long as one week after therapy may survive, and eggs deposited before therapy may survive for up to three weeks. The entire family is usually treated. Petroleum jelly may be applied topically to relieve itching.

Treatment to prevent reinfection includes careful attention to personal hygiene, especially the washing of hands and fingernails, clothing and bed linens.

Investigational Therapies

Information on current clinical trials is posted on the Internet at www.clinicaltrials.gov. All studies receiving U.S. government funding, and some supported by private industry, are posted on this government web site.

For information about clinical trials being conducted at the NIH Clinical Center in Bethesda, MD, contact the NIH Patient Recruitment Office:

Tollfree: (800) 411-1222

TTY: (866) 411-1010

Email: prpl@cc.nih.gov

For information about clinical trials sponsored by private sources, contact:




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Berkow R., ed. The Merck Manual-Home Edition, 2nd ed. Whitehouse Station, NJ: Merck Research Laboratories; 1997:.

Mandell GL, Bennett JE, Dolan R, eds. Mandell, Douglas and Bennett's Principles and Practice of Infectious Diseases. 4th ed. Churchill Livingstone Inc. New York, NY; 1995:2528, 479-80.


St Georgiev V. Chemotherapy of enterobiasis (oxyuriasis). Expert Opin Pharmacother. 2001;2:267-75.


Tandan T, Pollard AJ, Money DM, et al. Pelvic inflammatory disease associated with Enterobius vermicularis. Arch Dis Child. 2002;86:439-40.

Olivares JL, Fernandez R, Fleta J et al. Vitamin B12 and folic acid in children with intestinal parasitic infection. J Am Coll Nutr. 2002;21:109-13.

Ibarra J. Threadworms: a starting point for family hygiene. Br J Community Nurs. 2001;6:414-20.

Parija SC, Sheeladevi C, Shivaprakash MR, et al. Evaluation of lactophenol cotton blue stain for detection of eggs of Enterobius vermicularis in perianal surface samples. Trop Doct. 2001;31:214-15.

Matsushita M, Takakuwa H, Nishio A, et al. Pinworm Infection. Gastrointest Endosc. 2001;53:210.

Birbeek GL The benefits of screening must outweigh the risks and costs. West J Med. 2000;172:308-09.

Lohiya GS, Tan-Figueroa L, Crinella FM, et al. Epidemiology and control of enterobiasis in a development center. West J Med. 2000;172:305-08.


Fact Sheet: Pinworm Infection. CDC Division of Parasitic Diseases. Last reviewed August 15, 1999. 3pp.


Enterobiasis. Parasites and Health. Last Modified: 04/09/2002. 2pp.


Enterobiasis. Parasites and Health. Last Modified: 12/13/2002. 1p.


Wolfram W. Enterobiasis. eMedicine. Last Updated: May 14, 2003. 6pp.



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For a Complete Report

This is an abstract of a report from the National Organization for Rare Disorders, Inc.® (NORD). Cigna members can access the complete report by logging into myCigna.com. For non-Cigna members, a copy of the complete report can be obtained for a small fee by visiting the NORD website. The complete report contains additional information including symptoms, causes, affected population, related disorders, standard and investigational treatments (if available), and references from medical literature. For a full-text version of this topic, see http://www.rarediseases.org/search/rdblist.html.