What is Anisakiasis?
Anisakiasis is a disease of the stomach and small intestines caused by infection with a parasitic nematode (a type of worm). The diagnosis of anisakiasis is usually made by detecting the 2 cm long larvae in the intestines during a medical examination; it can also be found in surgically removed tissue. Most anisakiasis cases are reported in Japan, Western Europe (particularly Scandinavia), and the Pacific coast of Latin America where raw or undercooked seafood is eaten regularly.
How do you get it?
You can get anisakiasis by eating uncooked or inadequately treated (salted, marinated, smoked, or frozen) octopus, squid, and saltwater fish (commonly, salmon).
What are the symptoms of Anisakiasis?
The symptoms of anisakiasis include sudden, severe stomach pain that sometimes mimics appendicitis, often with nausea, and vomiting.
When do symptoms start?
The symptoms usually begin within 6 hours of eating raw or inadequately treated seafood.
What is the treatment for Anisakiasis
Most patients improve spontaneously without specific therapy. If necessary, the worm can be removed surgically. Prescribed medications can be effective if surgery is not needed.
If you get anisakiasis once, can you get it again?
Yes. Second infections with anisakiasis have been reported.
Should an infected person be excluded from work or school?
No. Direct person-to-person transmission does not occur.
How can you keep from getting it?
- Thoroughly cook or freeze all seafood. The infectious larval stage of the worms can be killed by cooking at 140 °F (60°C) for at least 10 minutes.
- If fish are to be frozen, make sure that they are frozen for more than 5 days at temperatures at or below 5°F (-4°C) to ensure killing of the parasite.
- Clean all fish as soon as possible after they are caught to reduce the chance that larvae might migrate into the flesh of the fish.


