The Anisakis worm is a parasite that can cause nasty infections in humans who enjoy eating raw fish.
It is 2 cm long and is sometimes coughed up after ingesting it in raw or undercooked fish.
Adult worms are found in the stomach of marine mammals, and their eggs are passed in the feces.
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After the larvae are hatched, they are ingested by shellfish.
Infected shellfish get eaten by fish and squid, where the larvae make their way into the muscle tissues.
Ingestion of infected fish or squid by other fish allows the spread of the infection.
Ingestion by marine mammals is necessary for the larvae to develop into adult worms.
Penetration of the worms into the intestinal tissue causes anisakiasis.
You’re at risk if you eat raw or undercooked seafood.
The US reports fewer than 10 diagnosed cases each year.
Diagnosis is made by gastroscopic or histopathologic examination of biopsy tissue.
Human infection is a dead end in the parasites life cycle.
The worms are usually eliminated or expelled from the intestines within 3 weeks of infection.
Treatment and Prevention
Treatment is surgical or endoscopic removal of the parasites.
The FDA has provided several guidelines for retailers who sell fish intended to be eaten raw.
Frequently Asked Questions
Symptoms of anisakiasis can include violent abdominal pain, nausea, and vomiting.
Larvae of the Anisakis worm can be carried by raw or undercooked marine fish and squid.
Some examples include cod, flounder, fluke, haddock, herring, monkfish, and Pacific salmon.
Yes, freezing fish for certain lengths of time should kill its parasites.
Anisakiasis is treated by removing the parasite through either endoscopy or surgery.
This may be necessary if the Anisakis worm is not naturally expelled from the body and causes intestinal issues.
European Academy of Allergy and Clinical Immunology.Anisakis.
Centers for Disease Control and Prevention.Anisakiasis.
