Occurrence and survival of the larval nematode Anisakis sp. in the flesh of fresh, frozen, brined, and smoked pacific herring, Clupea harengus pallasi.

Two hundred and twenty Pacific herring (Clupea harengus pallasi) from Yaquina Bay, Oregon, were divided into five groups to test the effects of various methods of handling and processing (fresh, frozen, brined, cold smoked, and cold smoked-gibbed) on the occurrence and survival of Anisakis larvae in the flesh. Viscera and flesh were digested separately using a pepsin-HC1 technique, and counts were taken of Anisakis larvae. Parasite loads were statistically largest in the flesh of frozen, brined, and smoked fish. Smoked fish harbored the greatest proportions of larvae in the flesh. Human consumption of brined or cold smoked Pacific herring represents a potential public health hazard.