ISA Virus UpdateApril 16, 2012
The initial 38 Wild Fish Conservancy samples sent to the World Organization for Animal Health (OIE) reference lab in Norway (Dr. Are Nylund), comprised of gill and heart tissues from Chinook, chum and sockeye salmon, taken this past fall from the Skagit and Snohomish river systems and rivers of the Olympic Peninsula, were negative for infectious salmon anemia virus (ISAV). However, all but one of the sockeye samples (all from the Olympic Peninsula) showed signs of disease and were positive for infectious hematopoietic necrosis virus (IHNV), another pathogen of salmonids common in the Pacific Northwest (for more information, see the link below).
Recently, ISAV was detected in 5 of 29 Atlantic salmon gills in fish purchased from the Canadian supermarket chain T&T by Alexandra Morton and the Salmon Are Sacred group in B.C.; a chum salmon from the Vedder River was also positive (testing was done by the OIE reference lab in eastern Canada). Staff at the supermarket were unable to cite the source of the fish, but these detections raise concerns that infective salmon tissues are being imported to or exported from British Columbia. Canadian officials claimed that the samples could not be re-tested by government labs, although the fish were stored on ice and the samples were in excellent condition. They also continue to dispute the “testing methods”, although their own internationally recognized expert on ISAV, Dr. Fred Kibenge, ran the tests. Their press release said, in part:
“March 12, 2012, Ottawa: The Government of Canada has been notified of a suspected infectious salmon anemia finding by a private laboratory based on samples collected in British Columbia. These tests have not been confirmed by the National Aquatic Animal Health Laboratory System (NAAHLS) laboratory, which uses internationally recognized test methods. Infectious salmon anemia is not a human health concern. According to the World Organization for Animal Health (OIE), the virus must be isolated and identified before infectious salmon anemia can be confirmed. Given the way the original samples were preserved, virus isolation will not be possible. There are additional concerns with the sampling and testing methods used.”http://www.inspection.gc.ca/about-the-cfia/newsroom/news-releases/salmon-disease/eng/1331593988662/1331594028592
It does not appear that we can rely on the B.C. government for factual information regarding ISAV; they continue to argue that “viral isolation” (i.e. isolating ISAV from cell culture) is required before they will admit that they have a positive result, despite the fact that several peer-reviewed journal articles have demonstrated that many strains of ISAV cannot be successfully cultured.
WFC staff and volunteers continue to sample salmon carcasses from western Washington for ISAV, where the likelihood of detection is high due to the proximity with British Columbia and the migration routes of salmon. We have also begun sampling Atlantic salmon gills from supermarkets in western Washington. However, it is expensive to have these samples analyzed by PCR, the most sensitive assay; with the added expense of mailing these samples to the OIE labs, each sample costs roughly $50 to process. Currently we have a backlog of roughly 80 samples that we need to have analyzed to determine if ISAV is present in salmon from western Washington; the total cost to have these samples analyzed is $4,000. To raise money to have these samples tested, we are initiating the "Adopt-A-Sample" program. Please consider making a donation to help us continue this important work. To donate click on the “Donate” button below.
For more information on IHNV, see the USGS Western Fisheries Research Center webpage.
For more information on the detections of ISAV in Canada, go to
For more general ISA virus information, visit the Infectious Salmon Anemia virus section of our website.