A restricted zone is to be established around the site.
Infectious salmon anemia (ISA) has been detected at a site run by Mowi in More and Romsdal county in the northernmost part of Western Norway, the Norwegian Food Safety Authority said on Thursday night.
The alarm was raised on 22 August by fish health company Patogen, after conducting PCR tests on fish samples from the site.
The Norwegian Veterinary Institute diagnosed ISA on 31 August after analysis of samples taken at the facility on 24 August.
The Norwegian Food Safety Authority confirmed the ISA diagnosis on 31 August on the basis of an inspection of the fish, signs of disease and analysis results from the Veterinary Institute.
In order to limit the spread of infection, restrictions have been imposed on the site, including a ban on moving fish without special permission.
ISA is a viral disease that can result in serious economic losses in the salmon farming industry.
The virus can cause severe anemia in salmon due to the bursting of red blood cells. Clinical signs in infected fish can include lethargy, swimming close to the water surface or the sides of cages, pale gills, swollen abdomen, and sometimes, internal and external hemorrhaging.
The disease is a concern for aquaculture operations because of its potential to cause high mortality rates and its impact on fish health and farm productivity.
