Ascariasis
Condition
(Roundworm)
Definition
Ascariasis is an infection. It can lead to problems in the lungs or digestive organs.
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Causes
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 when a person ingests the worm eggs. This can happen by putting dirty hands or fingers in the mouth or by eating vegetables or fruits that have not been peeled, washed, or cooked.
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 areas with poor sanitation. People who live in Asia and the western Pacific are at higher risk. The risk is also higher in children who are 5 to 15 years of age.
Exposure to contaminated soil is the biggest risk factor for ascariasis.
Symptoms
Most people do not have ascariasis symptoms. Those who do may have:
- A dry cough
- Fever
- Problems breathing, such as wheezing
- Belly cramps
- Vomiting
- Diarrhea
- Weight loss
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Diagnosis
The doctor will ask about symptoms and past health. You will also be asked about any recent travel. A physical exam will be done.
Tests may be done, such as:
- Stool (poop) tests—to look for signs of the parasites
- Blood tests—to look for signs of a parasitic infection
Pictures of the body may be taken. This can be done with:
- X-ray
- Ultrasound
Treatment
Ascariasis is treated with anti-parasitic medicine. Surgery may be needed if there are blockages in the digestive tract.
Prevention
The risk of ascariasis may be lowered by food safety and sanitation measures.
Centers for Disease Control and Prevention
World Health Organization
CANADIAN RESOURCES:
Public Health Agency of Canada
Travel and Tourism—Government of Canada
Centers for Disease Control and Prevention
World Health Organization
CANADIAN RESOURCES:
Public Health Agency of Canada
Travel and Tourism—Government of Canada
References
- Ascariasis. EBSCO DynaMed website. Available at: https://www.dynamed.com/condition/ascariasis.
- Ascariasis. Merck Manual Professional Version website. Available at: https://www.merckmanuals.com/professional/infectious-diseases/nematodes-roundworms/ascariasis.
- 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: https://www.cdc.gov/parasites/ascariasis.
Contributors
- David L. Horn, MD, FACP
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