Read this story from the New York Times on the recent discovery of wild Pacific sockeye infected with the European strain of the deadly ISA virus.

“A lethal and highly contagious marine virus has been detected for the
first time in wild salmon in the Pacific Northwest, researchers in
British Columbia said on Monday, stirring concern that it could spread there, as it has in Chile, Scotland and elsewhere. Farms hit by the virus, infectious salmon anemia, have lost 70 percent
or more of their fish in recent decades. But until now, the virus, which
does not affect humans, had never been confirmed on the West Coast of
North America”. (Oct. 17, 2011)

http://www.nytimes.com/2011/10/18/science/18salmon.html