New virus in B.C. salmon?
The never-ending spectacle of investigating the relationship between farmed and wild salmon continues in British Columbia, with the continuation of testimony for Justice Cohen, appointed by the federal government of Canada to look into the failed return of sockeye salmon to the Fraser River near Vancouver in 2009. The fact that a record number of salmon showed up to spawn the next year didn’t slow down the finger-pointing by environmentalists at the province’s salmon farming industry.
Despite thousands of attempts at isolating the ISA virus and other pathogens from their stocks, salmon farmers and their veterinarians and other scientists have never encountered the dreaded ISA virus in samples taken from farms in B.C. But miraculously, some environmental opponents to the industry with various scientific credentials recently announced with great fanfare that indeed the ISA virus had been found in wild B.C. salmon. The fact remains that no such virus has been isolated. But new light was shed on the factual situation during today’s testimony by four scientists that usually are considered credible, and where the possibility of an ISA-like virus might have been around before the first Atlantic salmon was ever farmed here, but without causing any form of disease outbreak in either farmed or wild stock.
Tamsyn Burgmann of The Canadian Press provides some background;
There are indications that for decades now salmon in British Columbia may have been carrying a virus that wiped out stocks in Norway and Chile, but experts don't know if it will have the same devastating results. Four pre-eminent fish scientists relayed their suspicions during an extraordinary meeting of the Cohen Commission, which has spent 21 months investigating the sharp decline of B.C.'s Fraser River sockeye. The commission reconvened after the alarming discovery by a Simon Fraser University professor of infectious salmon anaemia in two smolts in northern B.C.
Kristi Miller, who heads a molecular genetics lab for the federal Fisheries Department, joined two other Canadians and a Norwegian on a panel appearing before the commission. "I clearly believe that there is a virus here that is very similar to ISA virus in Europe, but we really do need to get a fuller sequence to get more information about how similar it is," said Miller. "Also, we have not established that it causes disease." Miller gave evidence Thursday in the first of three days of the special sitting to discuss infectious salmon anaemia. Her submissions came from research conducted in her Nanaimo, B.C., laboratory. She noted the testing procedures were not standard and differed from another government-funded lab on the East Coast, but suggested her tests could be more sensitive.
Miller told the inquiry that she has not only tested recent samples of fish, but went back into her massive archive and ran the same procedure on fish from 1986 and found a similar pattern. "Which suggests that not only has this been here for at least 25 years, but it's been here probably quite considerably longer than that," she said. Some research indicates Pacific salmon could be resistant to the virus.
ISA, an influenza-like virus, has killed millions of fish in Chile after it's believed to have been transported from Norway, where it was first discovered in the 1980s. Government scientists from the Department of Fisheries and Canadian Food Inspection Agency moved to assuage fears by conducting further tests. Along with the Fisheries Minister, they announced the virus had not been detected and said public agencies will nonetheless develop a new surveillance plan to watch more closely for fish diseases.
The panel of scientists agreed more research needs to be done. "In this case, I don't know where we are at this point because we do not have enough information, but it could really be that we are looking at another ISA that was there for a long time," said Nellie Gagne, a molecular biology scientist who leads a Department of Fisheries lab in Moncton, N.B. "It's an interesting theory that I'm keen to see more work done on." Gagne said her own lab had not turned up any samples she would consider positive, but noted that the lab uses "universal" test methods that look for known strains. "If there are others, we don't know about it," she said.
Fred Kibenge, who works at the Atlantic Veterinary College which runs the reference lab for the virus in P.E.I., conducted the initial tests that came up with positive results on two smolts publicized widely in October. He told the inquiry he believes the recent testing conducted by himself and Miller is "overwhelming" evidence of the virus. He also tried to substantiate an unpublished study from 2004 -- conducted in part by his wife -- that was leaked to media last month. It concluded an asymptomatic form of the virus was occurring in some wild-salmon species in the north Pacific. Kibenge noted the results that emerged from Miller's lab means that his wife's earlier tests may yet be credible.
However, one scientists came out strongly opposing the results found in Miller's lab. "We have a lot of indications that the virus could be present in Pacific salmon, but there is no hard evidence," said Are Nylund, a professor with the department of biology at the University of Bergen in Norway. Nylund, who has studied the virus for years, described Miller's testing procedures as "a bit strange." He did note he believes the virus could spread from eastern Canada, where it has infected Atlantic salmon, to the West Coast, similar to the theorized transfer of the virus from Norway to Chile.
