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Whipworm Infection



Richard D. Pearson

, MD, University of Virginia School of Medicine

Last full review/revision Sep 2020| Content last modified Sep 2020
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Whipworm infection is an intestinal infection caused by the roundworm Trichuris trichiura.

  • People acquire the infection by eating foods contaminated with soil that contains whipworm eggs or by swallowing eggs after having contact with contaminated soil.

  • People may have no symptoms or may have abdominal pain, loss of appetite, diarrhea, bleeding from the intestine, or anemia, depending on the severity of the infection.

  • Doctors usually diagnose the infection by identifying eggs in a stool sample.

  • Adequate sanitation and good personal hygiene help prevent spread of the infection.

  • An antiparasitic drug such as albendazole is used to treat the infection.

Trichuriasis is a common infection, occurring mainly in the subtropics and tropics, where poor sanitation and a warm, moist climate provide the conditions needed for Trichuris eggs to incubate in the soil. It also occurs in the southern United States. About 604 to 795 million people, mostly children, are infected worldwide.

Transmission of whipworm infection

People acquire the parasite by

  • Swallowing food contaminated by soil that contains eggs

  • Transferring eggs from their hands to their mouth after contact with contaminated soil

Children may swallow contaminated soil.

The larvae hatch in the small intestine, migrate to the large intestine, and embed their heads in the lining of the intestine. Each larva grows into a worm that is about 4 1/2 inches (11 centimeters) long and is estimated to live 1 to 2 years, although some may live longer. Female whipworms produce eggs, which are excreted in the stool.


Mild whipworm infections often cause no symptoms.

Abdominal pain, loss of appetite, and diarrhea occur when a large number of worms are present in the colon. Weight loss, bleeding from the intestine, and anemia may result, especially in children with heavy infections. Occasionally, a massive infection causes the rectum to protrude through the anus (rectal prolapse).


  • Examination of a stool sample

A doctor bases a diagnosis of trichuriasis on seeing the typical lemon-shaped eggs in stool samples examined under a microscope or occasionally by observing adult worms during a colonoscopy or proctoscopy (examination of the rectum with a viewing tube).

A complete blood count is done to check for anemia.


Prevention of whipworm infection depends on

  • Adequate sanitation (particularly sanitary toilet facilities)

  • Good personal hygiene

Hands should be washed before handling food, and unwashed fruits and vegetables should be avoided.

Sometimes a single large dose of albendazole or mebendazole is given to groups of people, particularly children, who are at risk of being infected with whipworms (and other worms spread through contaminated soil, such as hookworms and Ascaris). This treatment helps prevent complications of these infections.


  • Mebendazole, albendazole, or ivermectin (antiparasitic drugs that eliminate worms—anthelmintic drugs)

Mebendazole, albendazole, or ivermectin, taken by mouth, is used to treat whipworm infection. Mebendazole taken twice daily for 3 days is preferred for heavy infections.

Albendazole or ivermectin taken once a day for 3 days is an alternative.

Usually, none of these drugs is given to pregnant women because these drugs can harm the fetus.

If people have been to areas in Africa where Loa loa is transmitted, doctors check them for loiasis before giving them ivermectin because ivermectin can cause serious brain inflammation (encephalitis) in people with loiasis.

NOTE: This is the Consumer Version. DOCTORS: Click here for the Professional Version
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