Alaska Ponders ISA Outbreak in Wild Salmon Population

This is a serious threat to pacific salmon.  However, previous cases only involved farmed atlantic salmon.  Its introduction into the wild population is frightening, but the natural variation of wild pacific salmon offeres a much different environment than the unhealthy, pen raised counterpart.  The photo below shows lesions, which are typical of the ISA virus in atlantic salmon.

State officials say there is no reason to panic and that Alaska salmon are relatively safe from a deadly fish virus that has appeared for the first time in North Pacific waters.

“I would say the risk right now for Alaska salmon is low,” said Dr. Ted Meyers, a fish pathologist with the Alaska Department of Fish and Game.

Meyers added that the state is in sort of a holding pattern, awaiting more information.

The West Coast fishing industry was stunned last week when Canadian scientists at Simon Fraser University detected Infectious Salmon Anemia (ISA) in two wild sockeye smolts at Rivers Inlet in northern British Columbia. ISA is harmless to humans but it is the single most feared virus in the fish industry.

The highly contagious virus can quickly kill tens of millions of fish confined in net pens, as happened with Chile’s multibillion-dollar farmed salmon industry in 2007. Fish farms in Norway and Scotland also have suffered lethal ISA outbreaks. The big unknown is how vulnerable wild Pacific salmon and also herring might be. Virus experts called the news alarming but cautioned that the test results do not indicate how wide-ranging the virus is, and the results have not been confirmed by additional testing.

“Anytime ISA is present, there is potential for an outbreak,” said Jim Winton, a microbiologist at the USGS Western Fisheries Research Center in Washington. “The virus has great potential to mutate, which raises concerns about its impact on wild salmon.”

Neighboring U.S. senators want answers fast.

Sens. Lisa Murkowski and Mark Begich of Alaska and Maria Cantwell of Washington state have already asked Congress to require federal agencies to assess the ISA virus’ risks to Pacific fish and report back in six months.

via State isn’t panicking over ISA salmon virus: Laine Welch | Alaska news at

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