The salmon farm in Skjervoy, Nord Troms, Troms confirmed the outbreak to the OIE on the 29 May.
Of the 1,224,100 Atlantic salmon susceptible, the outbreak led to 100,000 cases, resulting in the death of 50,000 and of 138,5000 salmon to be destroyed.
"A ban on the movement of fish without special permission has now been implemented," said district chief Knut Øystein Johansen's.
The source of the outbreak is still unknown.