Life Cycle

http://en.wikipedia.org/wiki/Image:Anisakiasis_01.png

Anisakiasis life cycle.

1. Excretions from marine mammals contain unembryonated parasite eggs.
2. In the ocean the eggs become embryonated. Larval development begins.
3. Eggs hatch and larva continue growth in the water.
4. Crustaceans consume larva and Anisakid maturation continues.
5. Marine fish and squid feed on infected crustaceans. The larvae reside in the fish’s muscle tissue.
6. Humans and marine mammals that ingest infected undercooked or raw seafood (containing 3rd stage larvae) may become infected. Inside the bodies of marine mammals and humans the larva will molt two more times. The larvae will metamorphose into adult worms in the stomach and small intestines.

Reference: http://www.dpd.cdc.gov/dpdx/HTML/Anisakiasis.htm