Ascaris suum

nematode

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Last updated

July 22, 2026

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Ascaris suum is a type of nematode, commonly known as a roundworm, that can parasitize the intestines of mammals, including pigs and, less commonly, humans. These worms can grow quite large, reaching up to about 40 cm (16 inches) in length.12

The infection, called ascariasis, is widespread, affecting hundreds of millions globally, particularly in areas with poor sanitation. While many infected individuals show no symptoms, heavy infestations can lead to serious health issues, especially in children, such as malnutrition, stunted growth, and intestinal blockages. The life cycle involves ingesting eggs, which hatch into larvae that migrate through the body, eventually maturing into adult worms in the small intestine.2

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ascariasis
…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, affecting an estimated 807 million to 1.2…
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…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, affecting an estimated 807 million to 1.2…
Read More