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Anisakiasis
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Anisakiasis

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Anisakiasis is infection with larvae of worms of the genus Anisakis and related genera such as Pseudoterranova. Infection is acquired by eating raw or poorly cooked saltwater fish; larvae burrow into the mucosa of the GI tract, causing discomfort.

Anisakis is a parasite of the GI tract of marine mammals. Excreted eggs hatch into free-swimming larvae, which are ingested by fish and squid; human infection is acquired by ingestion of these intermediate hosts in a raw or poorly cooked state. Larvae burrow into the stomach and small bowel. Symptoms typically include abdominal pain, nausea, and vomiting; intestinal infection may create an inflammatory mass causing symptoms resembling Crohn's disease.

Diagnosis is usually made by upper endoscopy; stool examination is unhelpful, but a serologic test is available in some countries. Infection typically resolves spontaneously after several weeks but rarely persists for months. Endoscopic removal of the larvae is curative. Cooking to > 50° C (> 122° F) and freezing > 24 h destroy larvae; they may resist pickling, salting, and smoking.

Last full review/revision November 2005

Content last modified November 2005

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