The outbreak was reported by Dr Keren Bar-Yaacov, Chief Veterinary Officer, Legislation, Norwegian Food Safety Authority to the OIE.
From an epidemiological point of view, the Norwegian Food Safety Authority (NFSA) at present considers the ISA outbreak in Vesteralen likely to be a first occurrence in this geographical area.
Infectious salmon anaemia (ISA) was already present in Nordland in February and April 2013. However, at that time the disease did not affect the same area in which this notified outbreak has occurred.
Therefore the NFSA assumes the currently reported outbreak is not a reoccurrence of ISA disease. The previous occurrences of ISA outbreaks took place in a quite different area within Nordland, the current outbreak occurs at a distance of more than 110 km from other ISA-outbreaks.
In total, there are 1,236,000 susceptible salmon, with 3,000 confirmed cases, resulting in 540 deaths.
The cause of the outbreak remains unknown.