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Trichuriasis

(Whipworm Infection; Trichocephaliasis)

By

Richard D. Pearson

, MD, University of Virginia School of Medicine

Last full review/revision Mar 2019| Content last modified Mar 2019
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Trichuriasis is infection with Trichuris trichiura. Symptoms may include abdominal pain, diarrhea, and, in heavy infections, anemia and undernutrition. Diagnosis is by finding eggs in stool. Treatment is with mebendazole, albendazole, or ivermectin.

Trichuriasis is the 3rd most common roundworm infection. An estimated 604 to 795 million people are infected worldwide. Trichuris trichiura occurs principally in developing tropical or subtropical areas where human feces is used as fertilizer or where people defecate onto soil, but infections also occur in the southern United States. Children are most affected.

Infection is spread via the fecal-oral route. Ingested eggs hatch and enter the crypts of the small bowel as larvae. After maturing for 1 to 3 months, the worms migrate to the cecum and ascending colon, where they attach to the superficial epithelium, mate, and lay eggs.

Adult worms are estimated to live 1 to 2 years, although some may live longer.

Symptoms and Signs

Light Trichuris infections are often asymptomatic.

Patients with heavy infections may have abdominal pain, anorexia, and diarrhea; weight loss, anemia, and rectal prolapse may result, particularly in children.

Diagnosis

  • Microscopic examination of stool

Diagnosis of trichuriasis is made by microscopic examination of stool; the characteristic lemon-shaped eggs with clear opercula at both ends are readily apparent. When anoscopy, proctoscopy, or colonoscopy is done for other indications, wiggling adult worms may be seen protruding into the bowel lumen.

Complete blood count (CBC) is done to check for anemia.

Treatment

  • Mebendazole

  • Alternatively, albendazole or ivermectin

Mebendazole 100 mg orally twice a day for 3 days is recommended. A single dose of mebendazole 500 mg has been used in mass treatment programs. Alternatives are albendazole 400 mg orally once a day for 3 days or ivermectin 200 mcg/kg orally once a day for 3 days. These drugs should usually not be used during pregnancy.

If treatment with ivermectin is planned, patients should be assessed for coinfection with Loa loa if they have been in areas of central Africa where it is transmitted; ivermectin can induce severe reactions in patients with high levels of Loa loa microfilariae.

Prevention of trichinosis is possible through good sanitation, handwashing, and good personal hygiene.

Key Points

  • Trichuriasis occurs principally in developing tropical or subtropical areas where human feces is used as fertilizer or where people defecate onto soil, but infections also occur in the southern United States, mainly in children.

  • Infection is spread via the fecal-oral route.

  • Light infections are often asymptomatic; heavy infections may cause abdominal pain, anorexia, diarrhea, and, in children, weight loss, anemia, and rectal prolapse.

  • To diagnose trichuriasis, examine a stool sample for the characteristic lemon-shaped eggs with clear opercula at both ends.

  • Treat with mebendazole (recommended); albendazole and ivermectin are alternatives.

  • If treatment with ivermectin is planned, assess patients for coinfection with Loa loa if they have been in areas of central Africa where it is transmitted; ivermectin can induce severe reactions in patients with high levels of Loa loa microfilariae.

Drugs Mentioned In This Article

Drug Name Select Trade
ALBENZA
No US brand name
STROMECTOL
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NOTE: This is the Professional Version. CONSUMERS: Click here for the Consumer Version
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