Scientists divided over threat to Pacific Northwest salmon – infectious salmon anemia, or ISA.

adn.com – There is no doubt that the disease can wreak havoc. First described in Norway in the mid-1980s, it has flared on fish farms from Maine and the eastern coast of Canada to Scotland and Chile, which reported a new outbreak last month. The virus is also capable of mutating rapidly, which scientists on all sides of the issue say increases the need to keep an eye on it. Its victims can be seen gasping at the surface, lethargic and often swollen with fluids; mortality can reach 90 percent. continued