Anisakis

What is Anisakis?

Anisakis is a genus of parasitic nematodes (roundworms) commonly found in certain types of marine fish and squid. When humans consume raw or undercooked fish containing these larvae, the parasites can cause infections and allergic reactions. This parasite is most commonly associated with sushi, sashimi, ceviche, and other raw seafood dishes.

Why do I have an intolerance?

Some individuals develop an allergy to the proteins in Anisakis. For those sensitive to these proteins, even trace exposure can lead to allergic reactions, ranging from mild symptoms like hives and gastrointestinal distress to severe reactions such as anaphylaxis. People may also experience “Anisakiasis,” where the larvae invade the gastrointestinal tract, causing intense abdominal pain, nausea, and vomiting. In some cases, the allergic reaction can occur even with thoroughly cooked fish, as the allergenic proteins remain active.

What can I do about it?

To prevent Anisakis exposure, avoid eating raw or undercooked fish, particularly in regions where Anisakis is common. Freezing fish before consumption can kill Anisakis larvae, as required by food safety regulations in many countries. Those with severe reactions should consider carrying an epinephrine auto-injector and seek guidance from an allergist to determine which seafood products are safe to consume.