Most people infected with ascariasis have no symptoms. Moderate to heavy infestations cause various symptoms, depending on which part of your body is affected.

In the lungs

After you ingest the microscopic ascariasis eggs, they hatch in your small intestine and the larvae migrate through your bloodstream or lymphatic system into your lungs. At this stage, you may experience signs and symptoms similar to asthma or pneumonia, including:

  • Persistent cough
  • Shortness of breath
  • Wheezing

After spending six to 10 days in the lungs, the larvae travel to your throat, where you cough them up and then swallow them.

In the intestines

The larvae mature into adult worms in your small intestine, and the adult worms typically live in the intestines until they die. In mild or moderate ascariasis, the intestinal infestation can cause:

  • Vague abdominal pain
  • Nausea and vomiting
  • Diarrhea or bloody stools

If you have a large number of worms in your intestine, you might have:

  • Severe abdominal pain
  • Fatigue
  • Vomiting
  • Weight loss or malnutrition
  • A worm in your vomit or stool

When to see a doctor

Consult your doctor if you have persistent abdominal pain, diarrhea or nausea.

April 23, 2015

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