Health monitoring of wild fish

The Norwegian Veterinary Institute monitors the occurrence and distribution of pathogens in wild salmonids.

The overarching goal of the health monitoring program for wild anadromous salmonids is to examine the occurrence and sources of pathogenic agents in wild salmonids. The National Veterinary Institute is responsible for the freshwater phase of the program while the Institute of Marine Research is responsible for the marine phase.


Heart and Skeletal Muscle Inflammation (HSMI) caused by piscine orthoreovirus (PRV1) is a common viral diseases of farmed Atlantic salmon in Norway. A related virus, called PRV3, is present at all levels of the rainbow trout production cycle in Norway and is associated with HSMI-like lesions in this species. In 2017, the objective of the health monitoring program in wild salmonids was therefore to investigate the occurrence of PRV3 in wild salmonids.

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