IHN virus gone from BC farms
Extensive testing shows no sign of the virus that caused the culling of Atlantic salmon from a farm on the west coast of Vancouver Island. Two farms with previous low findings get clean bill of health
FishfarmingXpert, Odd Grydeland, June 5, 2012
While salmon farmers in British Columbia are still nervous about the recent presence of the feared virus causing Infectious Hematopoietic Necrosis in Atlantic salmon, they are breathing a little easier after one farm owned by Grieg Seafood and another by Mainstream Canada both came through with negative results from sampling by government agencies. Both farms had been issued quarantine restrictions following previous low level findings indicating the presence of the virus.
All affected salmon farming companies have been very open with information about what has been happening at their farms, and all have provided samples as requested by the Canadian Food Inspection Agency (CFIA), the responsible authority for farmed animal health. Mainstream issued the following statement earlier today;
As of today, all of Mainstream Canada’s farms have been tested for the IHN virus, and all tests have come back negative. Since the Infectious Haematopoietic Necrosis (IHN) virus was first detected at Dixon Bay farm May 14, Mainstream has done extensive sampling at all the company’s farm sites. One of these samples, taken from Bawden Point farm, showed a “weak positive” for the IHN virus. The CFIA did two more rounds of sampling and testing, one week apart, at Bawden Point farm. All these samples have tested negative for IHN virus.
The quarantine on Bawden Point farm has since been lifted by CFIA. All fish at this site look healthy, mortality remains very low and no clinical signs of IHN virus have been detected. “This is good news for us, but we will stay on alert and maintain very strict bio-security measures and keep our farms isolated, while frequently testing for the virus,” said Fernando Villarroel, Mainstream Canada’s managing director. “We are hopeful that our quick and decisive action worked to prevent this virus from spreading to our other farms.”
During internal routine testing, Mainstream Canada’s Dixon Bay farm north of Tofino tested positive for the IHN virus on May 14, 2012. On May 17, the company began depopulating fish from the site and by the evening of May 21, the site was empty. Dixon Bay farm is still under quarantine while it is cleaned to CFIA’s standards. Bawden Point farm is located in Herbert Inlet north of Tofino.
And the largest producer of Atlantic salmon in BC- Marine Harvest Canada- issued this statement;
Marine Harvest Canada, BC's largest salmon farming company, confirms that all of its salmon farms have tested negative for the presence of Infectious Haematopoietic Necrosis (IHN) virus. "All 27 of our salmon farm sites have now been tested for presence of IHN," says Dr. Diane Morrison, Marine Harvest's Fish Health Director. "The tests have confirmed that IHN is not present at any of our farms."
IHN is commonly referred to as 'sockeye disease' and is naturally present in almost all stocks of sockeye salmon. While Pacific salmon (genus Oncorhynchus) are known to be resistant to the IHN virus, it can be fatal to Atlantic salmon (genus Salmo). Mainstream Canada (a BC salmon farming company not affiliated with Marine Harvest Canada) confirmed IHN at one Atlantic salmon farm on the West coast of Vancouver Island near Tofino. The fish were quickly and humanely disposed of to prevent spread to nearby farms. We are very happy that our farms are free from IHN," says Clare Backman, Marine Harvest's Sustainability Programs Director. "but transmission can come from passing wild fish, so we will continue to be diligent in regards to fish husbandry and biosecurity protocols to ensure our fish remain healthy."
The presence of IHN in wild and farm-raised salmon poses no risk to human health. Marine Harvest Canada produces one-half of British Columbia's largest agricultural export - farm-raised salmon. Its' processing plants, marine and land based operations are located on and around northern Vancouver Island and the village of Klemtu.
