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The Burden of Ascariasis

Adult female A. lumbricoides. Credit: DPDx

Adult female A. lumbricoides. Credit: DPDx

Ascariasis (roundworm) is aninfection of the intestines caused by a worm and is one member of a group of parasites known as the soil-transmitted helminths. Ascariasis is the most common human worm infection. More than 807 million people worldwide are infected with roundworm, and more than 60,000 die from the disease annually.

Adult roundworms can live in the body for one to two years, and grow as long as twelve inches and as thick as a pencil. A person infected by roundworm can initially have no symptoms. The infection is sometimes detected by observing the presence of worms in the stool. In severe cases, roundworm can cause intestinal problems, including blockage, particularly in children. Roundworm cannot be transmitted directly from person to person, because the worms require some time living in the soil to mature. Ascariasis is transmitted when a person accidentally eats something that has been contaminated by soil containing human feces.

More on: Ascariasis

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  • Page last reviewed: June 6, 2011 (archived document) The U.S. Government's Official Web PortalDepartment of Health and Human Services
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