Highlights & Basics
- Ascariasis is concentrated in developing countries of Asia, Africa, and Latin America.
- Acquired by ingesting eggs that are passed in human feces and mature in the soil.
- Diagnosis can be made in most cases by finding characteristic eggs in a stool sample.
- Treated with oral anthelmintic agents.
Quick Reference
History & Exam
Key Factors
Other Factors
Diagnostics Tests
Treatment Options
Definition
Epidemiology
Etiology
Pathophysiology
Images
Photograph of 2 Ascaris lumbricoides nematodes; the larger one on the left is female and that on the right is male. Adult females can grow to >12 in (30 cm) in length
A fertilized egg of the roundworm Ascaris lumbricoides at magnification x 400. Fertilized eggs are rounded, with a thick shell. Unfertilized eggs are elongated, are larger, have thinner shells, and are covered by a more visible mammillated layer, which is sometimes covered by protuberances
Diagram depicting the various stages in the life cycle of the intestinal nematode Ascaris lumbricoides
Photomicrograph depicting a fertilized egg of the parasite Ascaris lumbricoides
Laboratory technician holding a mass of Ascaris lumbricoides worms excreted by a child in Kenya
Citations
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World Health Organization. Preventive chemotherapy to control soil-transmitted helminth infections in at-risk population groups. September 2017 [internet publication].[Full Text]
Khuroo MS. Ascariasis. Gastroenterol Clin North Am. 1996;25:553-577.[Abstract]
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