New version of salmon virus may have started in B.C., expert says
Federal scientist says a possible new strain of a potentially deadly virus previously found only in foreign Atlantic-salmon fish farms has been discovered in Pacific salmon.
What may be a new variant of a potentially lethal virus that has decimated fish farms in eastern Canada, Chile and Europe has been found in B.C. wild salmon, an inquiry was told Thursday.
A federal scientist told the Cohen Commission infectious salmon anemia virus was found in B.C. sockeye and pink salmon tested at a Department of Fisheries and Oceans lab in Nanaimo.
That finding echoes a controversial October report by SFU researchers that claimed ISA - a virus previously found only in Atlantic salmon - had for the first time been detected in Pacific sockeye smolts.
The claim has been disputed by the Canadian Food Inspection Agency, which last month said it failed to find the virus after retesting the same samples.
The virus has two dominant strains - Canadian and European – scientists told the Cohen Commission, a federal investigation into the 2009 Fraser River sockeye fishery collapse. ISA is not necessarily lethal.
Those two variants have spread among and killed countless Atlantic salmon in Scottish, Norwegian, Chilean and New Brunswick fish farms since the European virus was first observed off the coast of Norway in 1984.
Fish farm critics say ISA is proof the industry is harming wild salmon in the province.
Kristi Miller, head molecular geneticist at a Department of Fisheries and Oceans lab in Nanaimo, B.C., said pink and sockeye salmon her lab tested for the salmon “flu” had a version of the virus divergent but 95 per cent similar to known strains.
“You can’t know things that you don’t have a (genetic) sequence for. And there is always a possibility that you will develop an assay” -- or test -- “that will pick up other variants you don’t know about,” she told the commission.
“And I believe that’s what has happened here.”
Miller also said her lab retested 1986 salmon samples and found those, too, had an ISA-like virus with a similar level of variation to fish from this year.
The advanced variance of the virus found in the 25-year-old samples may “suggest it’s been here longer than that,” she added.
Miller was one of four salmon virus experts testifying for the inquiry, which extended its hearing schedule to look into the virus.
Nellie Gagné, a scientist who runs a federal fisheries lab in Moncton, N.B., said strains of ISA have existed naturally for “thousands of years and they have evolved with their host.”
More testing needs to be done to establish the presence of ISA in B.C., she added.
Are Nylund, a Norwegian professor testifying via video link, questioned Miller’s lab techniques, saying they may have produced unreliable results.
The University of Bergen researcher said he’s not convinced the virus has hit the province.
He said there is currently “no hard evidence” to support that claim.
“Many indications it could be present in Pacific salmon but not hard evidence.”
The commission will hear two more days of evidence on the salmon virus. A final report is due next June.