Ascariasis
Key points
- Ascariasis is an infection caused by a parasitic roundworm, Ascaris lumbricoides.
- Ascariasis is the most common intestinal worm infection.
- Treatment Treatment includes medications that kill intestinal parasitic worms such as albendazole or mebendazole.
- Most people recover from the infection, even without treatment.
Definition
Ascariasis is an infection caused by a parasitic roundworm, Ascaris lumbricoides.
Causes, incidence, and risk factors
Ascariasis is the most common intestinal worm infection. It is found in association with poor personal hygiene, poor sanitation, and in places where human feces are used as fertilizer. Intake of food or drink contaminated with roundworm eggs causes infection.
The eggs hatch and release larvae within the intestine. The larvae then move through the bloodstream to the lungs, exit up through the large airways of the lungs, and are swallowed back into the stomach and intestines.
During movement through the lungs the larvae may produce an uncommon form of pneumonia called eosinophilic pneumonia. Once back in the intestines, they mature into adult roundworms. Adult worms live in the intestine where they lay eggs that are present in feces.
It is estimated that 1 billion people are infected worldwide. Ascariasis occurs in all ages, though children seem to be affected more severely than adults.
Symptoms
- Passing worms in stool
- Vomiting up worms
- Worms exiting through the nose or mouth
- Low-grade fever
- Cough
- Bloody sputum
- Wheezing
- Shortness of breath
- Skin rash
- Vomiting
- Stomach pain
Note: There may be no symptoms.
Signs and tests
- Stool ova and parasites exam
- An abdominal x-ray
- Routine blood counts (may show anemia)
- Malnutrition
Treatment
Treatment includes medications that kill intestinal parasitic worms such as albendazole or mebendazole. If there is a blockage of the intestine caused by a large number of worms, another medication can make the worms relax and pass through the intestine. This will relieve the obstruction.
Expectations (prognosis)
Frequently asked questions
What is ascariasis?
Ascariasis is an infection caused by a parasitic roundworm, Ascaris lumbricoides.
What are the risk factors for ascariasis?
Ascariasis is the most common intestinal worm infection. It is found in association with poor personal hygiene, poor sanitation, and in places where human feces are used as fertilizer. Intake of food or drink contaminated with roundworm eggs causes infection. The eggs hatch and release larvae within the intestine. The larvae then move through the bloodstream to the lungs, exit up through the large airways of the lungs, and are swallowed back into the stomach and intestines. During movement through the lungs the larvae may produce an uncommon form of pneumonia called eosinophilic pneumonia. Once back in the intestines, they mature into adult roundworms.
What are the symptoms of ascariasis?
- Passing worms in stool
- Vomiting up worms
- Worms exiting through the nose or mouth
- Low-grade fever
- Cough
- Bloody sputum
- Wheezing
- Shortness of breath
- Skin rash
- Vomiting
- Stomach pain Note: There may be no symptoms.
What is the outlook for ascariasis?
Written and revised by
Andrey Nailor, M.D.
Our doctors write and review articles for accuracy and keep them up to date.
health.am provides general information, not medical advice. Always consult a qualified health professional about your own health.