ISA virus in British Columbia?
ISA virus is one of many fish pathogens that are notifiable under Canadian regulations and by the World Organization for Animal Health (OIE). Like many other, normally harmless viruses, it has shown an ability to mutate and subsequently cause disease in farmed Atlantic salmon around the Atlantic Ocean and most recently in Chile. Testing for the presence of ISAV in farmed Atlantic salmon has been conducted in B.C. for years, and almost 5,000 samples taken over the past eight years have failed to detect the virus.
Experiments conducted in controlled laboratory settings with exposure to the virus have failed to cause disease in any of the five Pacific salmon species found in British Columbia, while high levels of ISAV injected in Rainbow trout caused some mortality, according to Dr. Gary Marty, Fish Pathologist with the B.C. Animal Health Centre in Abbotsford. Dr. Marty also told FishfarmingXpert that the Canadian Food Inspection Agency (CFIA), which received the report of the findings from the AVC, has yet to confirm the diagnosis of ISAV from two samples out of 48 taken from juvenile sockeye salmon smolts in Rivers Inlet on B.C.’s mainland north of Vancouver Island.
In a statement issued today, the B.C. Salmon Farmers Association expressed concern about the well-being of its members’ fish stocks if this finding of ISAV in B.C. waters is confirmed. "Farm-raised Atlantic salmon, unlike their Pacific cousins, are susceptible to ISA, so this is a concern for our operations, but much less likely to be an issue for the different Pacific species," said Stewart Hawthorn, Managing Director for Grieg Seafood. "If these results are valid, this could be a threat to our business and the communities that rely on our productive industry."
The statement also made reference to the current regulatory regime in place to avoid the unintentional transfer of pathogens with genetic material from other parts of the World; Extensive egg importation regulations were implemented years ago to ensure that disease is not imported to BC waters. Experts testified at the Cohen Commission of Inquiry into the Decline of Fraser River Sockeye Salmon that these regulations were strong and proactive in reducing the risk of disease. Testing done by third party researchers in the past on wild Sockeye have returned negative results for ISA as well. Biosecurity protocols both within each company and across the industry also protect the health of wild and farmed fish.
Long-term critics of the salmon farming business in B.C. were quick to point fingers at the industry, suggesting that this (exotic disease) “could have a devastating impact on wild salmon in B.C.” (Simon Fraser University Professor Rick Routledge).
