Parasites are common in wild fish from the sea. This is particularly true for the larvae of certain parasitic nematodes. The most important species in our waters is Anisakis simplex which may cause acute gastrointestinal illness if accidentally eaten alive. Parasitic nematode will die, however, at freezing, frying, boiling or strong salting for a extended periods. In Norway, farmed Atlantic salmon (Salmo salar) has long been excempted from the so-called freezing requirement since the risk of farmed salmon to contain nematodes, was rated negligible. This is because the parasitic nematode life cycle is broken when the salmon exclusively is fed on heat treated dry feed. The Norwegian Food safety authority (NFSA) now wants to continue the freezing exemption for farmed salmon in national regulations. The NFSA lacks, however, updated documentation showing that the fillets of farmed salmon do not pose a health hazard with regard to the presence of nematodes.
The project’s main objective is to establish the epidemiological baseline with regards to the occurrence of Anisakis in Norwegian farmed salmon as the basis for assessment of the exemption from the freezing requirement before raw consumption. In addition to being an important contribution to the revision of existing regulations, the project will provide increased knowledge of important factors affecting the occurrence of Anisakis in Norwegian cultured salmon.