Infectious salmon anemia - Canada (04): (BC), questioned
ProMed, MailDate: Thu 10 Nov 2011
Source: Paul Kitching [edited]
I would also like to correct your report that salmon infectious anaemia [ISA] virus has been found in British Columbia. There has been only an unconfirmed report from the ISA reference laboratory in Prince Edward Island. The original PCR test on a sample of 48 Sockeye salmon had reported a positive result for the European strain of ISA, but this has not been supported by any sequencing of the PCR product, isolation of live virus or examples of disease in the farmed Atlantic salmon (in which it is associated with disease). The provincial laboratory in Abbotsford has tested over 4000 farmed Atlantic farmed salmon as part of a regular health audit, and many samples from different species of wild Pacific salmon without finding any evidence of ISA virus associated disease.
The 48 samples have been retested by the federal laboratory and an independent laboratory in Norway. No sequence consistent with ISA virus was found in any of these samples.
Up until now, we considered pacific salmon resistant to ISA virus infection and disease. In fact, the 1st laboratory reporting ISA in Pacific salmon was the PEI [Prince Edward Island] laboratory.
The claim that ISA virus is now circulating in 4 species of wild Pacific salmon, taken almost at random, without any sequence data to support the announcement is remarkable, and makes little virological, epidemiological, or statistical sense, and I would caution ProMED readers against taking what has been reported below as scientifically validated evidence.
-- Paul Kitching Provincial Chief Veterinary Officer British Columbia Canada
[This communication agrees with the previous ProMED-mail post archive no. 20111110.3335 indicating that there is no conclusive evidence for infectious salmon anemia in the fish in question.
