by Scholten A


Ascariasis is an infection. It can cause problems in the lungs or digestive organs.

Digestive Tract and Lungs
Digestion tract and Lungs 3D
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Ascariasis is caused by roundworm parasites. Their eggs are found in the stool of infected people and animals. The eggs can also be in soil. They enter the body from hand to mouth.

Roundworm eggs hatch in the stomach. The baby worms may move to the liver and lungs. They can cause a type of pneumonia. They can also grow into adult worms in the stomach and intestines.

Risk Factors

Roundworms are most common in places with poor sewage control. The risk of getting sick is highest in Asia and the western Pacific.

Risk is also higher if exposed to soil or water with roundworm eggs. This can happen with:

  • Young children who play in it
  • Eating food grown in or washed in it
  • Drinking the water
  • Eating the soil


Most people do not have symptoms. Those who do may have:

Lung problems, such as:

  • Dry cough
  • Fever
  • Wheezing
  • Breathing problems

Bowel problems, such as:

  • Belly cramps
  • Vomiting
  • Diarrhea
  • Weight loss

The worms can also cause problems in the gallbladder, liver, pancreas, and appendix.

Inflammed appendix
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The doctor will ask about your symptoms, health and travel history. A physical exam may be done. Tests may be:

  • Stool tests
  • Blood tests
  • Imaging tests, such as:


Medicines treat the roundworm parasites. Surgery may be needed if there are blockages in the digestive tract.


The risk of infection may be lowered by food safety and sanitation measures.


Centers for Disease Control and Prevention 

World Health Organization 


Public Health Agency of Canada 

Travel and Tourism—Government of Canada 


Ascariasis. EBSCO DynaMed website. Available at: Accessed February 4, 2021.

Ascariasis. Merck Manual Professional Version website. Available at: . Accessed February 2021.

Leung AK, Leung, AA, et al. Human ascariasis: an updated review. Recent Pat Inflamm Allergy Drug Discov. 2020;14(2):133-145.

Parasites—ascariasis. Centers for Disease Control and Prevention website. Available at: Accessed February 4, 2021.

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