January 01, 2012

 

 Canada can't confirm ISA in BC salmon.

Posted on December 15, 2011
 

Canadian inspectors said in November their tests provided no evidence that infectious salmon anemia was present in British Columbia.

Dr. Cornelius F. Kiley, director of the Canadian Food Inspection Agency's Aquatic Animal Health Division, said his agency and Fisheries and Oceans Canada were still investigating reports that the infectious salmon anemia virus had been found in Pacific salmon caught in the province. But "there have been no confirmed cases of infectious salmon anemia in wild or farmed salmon in British Columbia." A final report is pending, he said.

"Testing in support of this investigation has been ongoing since mid-October, when a laboratory at the Atlantic Veterinary College of the University of Prince Edward Island reported that it had detected the virus," he said. The college's diagnostic laboratory on Prince Edward Island is a World Organisation for Animal Health (OIE) reference laboratory for infectious salmon anemia.

Rick Routledge, PhD, a statistics professor at Simon Fraser University, and marine biologist Alexandra Morton, PhD, reported Oct. 17 that the internationally reportable disease was found in two of 48 wild sockeye salmon smolts collected during a study on the collapse of the sockeye population in the Rivers Inlet, which is on the central coast of the province. The diagnosis was made at the Atlantic Veterinary College.

Infectious salmon anemia has caused high morbidity and mortality among Atlantic salmon, and outbreaks have occurred in the northeastern U.S. and eastern Canada.

In a Nov. 8 conference call with news media, Dr. Kiley was among governmental officials who said tests on samples from hundreds of fish since the report also have not provided evidence of infection.

Peter Wright, PhD, manager of the National Aquatic Animal Health Laboratory System for Fisheries and Oceans Canada, said in the call that, although the Atlantic Veterinary College has reported two positive test results, the college has not provided evidence of successful virus isolation or sequencing data that could be used to confirm the presumptive positive findings.

Dr. Wright further explained in a message that government investigators were not able to test cardiac samples from the 48 original smolts because no material was left after the college's tests. The investigators obtained negative test results with kidney RNA extracts, which had partly degraded. He noted that a lab in Norway produced a single weak positive result through molecular assays on gills from the 48 smolts, but he said the samples were of poor quality and the results couldn't be repeated.