roundworm

nematode species, Ascaris lumbricoides

Also known as: Ascaris lumbricoides

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Last updated

July 23, 2026

Quick Summary

nematode Nematode (*Ascaris lumbricoides*).

Ascaris lumbricoides is a species of intestinal roundworm that infects humans and other mammals. It is a parasitic worm, typically large, with a mouth surrounded by three lips. This roundworm is a common human parasite, with over 25 percent of the world's population infected, and it causes an estimated 20,000 deaths annually. A similar worm, A. suum, infects pigs and may be the same species as the human parasite.1

Ascariasis, the infection caused by Ascaris, is widespread, affecting between 807 million and 1.2 billion people globally. While many infected individuals show no symptoms, heavy infestations can lead to serious complications, especially in children, including malnutrition, stunted growth, and intestinal obstruction. The infection cycle begins with the ingestion of fertilized eggs, which then develop into larvae that migrate through the body, eventually maturing into adult worms in the small intestine.2

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ascariasis
…ascariasis typically is caused by A. lumbricoides; the large roundworm of pigs, A. suum, can also cause illness in humans. Although persons infected with Ascaris worms often are asymptomatic, heavy infestation can cause severe complications, particularly in children, who may experience malnutrition, growth stunting, or intestinal obstruction. Ascariasis exists worldwide,
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…ascariasis typically is caused by A. lumbricoides; the large roundworm of pigs, A. suum, can also cause illness in humans. Although persons infected with Ascaris worms often are asymptomatic, heavy infestation can cause severe complications, particularly in children, who may experience malnutrition, growth stunting, or intestinal obstruction. Ascariasis exists worldwide,
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piperazine
…in the treatment of intestinal roundworm infection in humans and domestic animals (including poultry) and against pinworm infection in humans. It is administered orally, in repeated doses, usually as the citrate salt. Its action causes worms to be paralyzed and then eliminated in the stool.
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…in the treatment of intestinal roundworm infection in humans and domestic animals (including poultry) and against pinworm infection in humans. It is administered orally, in repeated doses, usually as the citrate salt. Its action causes worms to be paralyzed and then eliminated in the stool.
Read More