Tag Archives: alexandra morton

Environment, Health, News

Salmon Virus Cover Up? Blame Canada!

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Contaminated salmon? (Photo: MvB)

“A decade before this fall’s salmon-virus scare, a Canadian government researcher said she found a similar virus in more than 100 wild fish from Alaska to Vancouver Island,” reports Craig Welch in the Seattle Times.

Four researchers authored the paper, which studied “chum, coho, pink and sockeye salmon from the west coast of Vancouver Island, Southeast Alaska, and the Bering Sea between August 2002 and April 2003,” says the Canadian Press in the Huffington Post.

Field researcher Molly Kibenge found indications of the virus in 117 fish, though all were asymptomatic. That wasn’t terribly surprising: In a paper published in Diseases of Aquatic Organisms in 2001, where her husband Fred Kibenge was lead author, they had already concluded that wild salmon could contract–but weren’t in terrible danger from–ISAv:

Within Norway, Scotland and the Canadian east coast (considered the normal geographic distribution), ISAV has been documented to cause disease outbreaks only in marine farmed Atlantic salmon. Wild fish with virus but no disease are common (Nylund et al. 1999, Devold et al. 2000), suggesting that asymptomatic or mild infection usually occurs among wild fish in those regions.

With no particular urgency to the findings, the paper was filed away. However, back in October, the news broke that infectious salmon anemia had come to the West Coast–or at least it had according to researchers who were bucking the official Canadian government word on the subject. So the paper, which clearly disputed the official government word as well, was suddenly relevant.

Molly Kibenge tried to get permission to submit the paper for publication in a journal–which would have opened the results up to peer review, for good or bad–but fellow author Simon Jones, of the Aquatic Animal Health Section of the Pacific Biological Station, refused. “[A]ll attempts to isolate the virus into cell culture failed,” he reminded Kibenge, who would have needed no reminding because it has been very difficult to isolate the virus into cell culture, even when working from dead salmon from the enormous Chilean outbreak that decimated the farmed salmon industry there.

Molly and Fred Kibenge’s 2001 paper suggests that very thing: “It is possible that ISAV strains of low virulence and non-pathogenic strains grow poorly or not at all in currently available fish cell lines,” they wrote.

When reports of more ISAv surfaced in early November, the government shot back that its tests, supported by an independent lab in Norway, showed no such thing. The problem? The Norwegian scientists actually disagreed:

“Our results are not conclusive, but do suggest … that an ISA virus is present in wild populations of O. nerka (Pacific sockeye),” Dr. Are Nylund, a professor of biology at the University of Bergen, wrote in an email exchange with The Seattle Times.

This tempest in a cell culture is ironic given that Molly Kibenge’s research, if accurate, would tend to reduce fears about the virus being “unleashed” in Pacific salmon–they already have it, it would seem, and are managing nicely. (That’s not to rule out the likelihood that the virus could mutate into a more virulent strain.)

What remains true is that farmed salmon Atlantic salmon are particularly susceptible to the virus, due in part to the cramped conditions of said farms, just as the close quarters of cities are breeding grounds for human viruses. The Canadian government’s alleged attempt to protect them from media exposure to the virus will do nothing to prevent an actual outbreak if wild fish are acting as a reservoir.

Meanwhile, Alexandra Morton, the biologist who found the latest suspect salmon, has had it with the governmental line. In a letter to Minister Ashfield she says:

Show us your Moncton test results because your lab is the only one that cannot find ISA virus. I would also suggest you stop obsessing over the quality of the River Inlet samples and go out and get your own samples. You have an entire department at your disposal.

Environment, News, Politics, Science

More Reports of Salmon Virus Found in Canadian Waters

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Salmon at the Ballard Locks (Photo: MvB)

It is not often, I think, that Canadian environmentalists have recourse to shaming their government by pointing to the U.S. being out in front on an issue, but that is the case with the study of infectious salmon anemia (the ISA virus, or the salmon “flu” as we’re calling it). Activist-biologist Alexandra Morton, who sent the initial fish suspects in for questioning, writes on her blog:

It is a big deal to Canada whether this virus is here or not because it has impact on barriers to trade. This is not an issue of simple biology, this affects companies owned by the Norwegian government and others.

While there has been no comment at all from Fisheries and Oceans in BC, the US is taking this seriously.

Now, reports Seattlepi.com: “the ISA virus was found in the fins of three adult salmon–a Chinook, a chum and a coho–taken out of the Harrison River in the Fraser Valley early last month.” However, they go on to say, “additional testing on the [first] sockeye smolts, done at the University of Bergen in Norway, was not able to confirm the findings.”

Only one of the tests showed a fish with ISAv, and that was at the limits of detectability, so it was not really a smoking fin. (Somewhat embarrassedly, Morton writes that storing the fish in a “home-type freezer was not optimal” in terms of potentially preserving the virus in pristine condition.)

With new reports of ISAv, the atmosphere becomes more tense. “[S]imilar to the sockeye from River’s Inlet, the Coho in the Fraser River was infected with the European strain of ISA virus. But we see from this report that a chinook salmon and a chum salmon also tested positive,” notes Morton.

In a way, it’s strange that the salmon farming industry in BC has been downplaying the chance of ISA making its way into their fish stocks. For one thing, farmed salmon are, because of their close quarters, most susceptible to the virus becoming epidemic. For another, so far it’s farmed Atlantic salmon who are symptomatic for ISAv–wild Pacific salmon can be carriers but tend not to die from it. The concern, is that as the virus mutates, that could change, and wreak havoc on salmon hatcheries. But with farmed Atlantic salmon, the danger is present from day one.

You’d think that, with the contagiousness of ISAv well established, you could expect Canadian authorities to be justifiably paranoid about it slipping in with hatchery eggs. But Morton claims that, contrary to the government’s insistence:

Surface disinfection is a guideline, not a regulation and DFO is not sure if the fish farmers were doing it and the DFO Director General of Science waived the Fish Health Protection Regulations in 2004 to allow eggs from a hatchery that does not meet these regulations.

Our U.S. salmon senators have banded together, Republican and Democrat alike, to proffer an amendment, since passed, that says the U.S. will not wait to see what Canada finds, but will move quickly to perform its own testing and prepare for the virus’s arrival. “The amendment requires a report be delivered to Congress within six months which outlines surveillance, susceptibility of species and populations, gaps in knowledge, and recommendations for action,” says Seattlepi.com.

UPDATE: From the Vancouver Sun:

“There are no confirmed cases of ISA in wild or farm salmon in B.C.,” said Con Kiley, the Canadian Food Inspection Agency’s national aquatic animal health program director. […]

However, questions remain because of the poor quality of the samples and federal officials agreed more testing is needed.

“The supplementary results must be considered inconclusive because of the poor quality of the samples,” Kiley said.

“Additional testing will continue and the results will be provided when we are ready.”

A commenter responds to the news. Given the back-and-forth up north, U.S. citizens may be happy that our own tests will be underway to keep an eye out for the virus’s appearance.

Environment, Health, News, Science

Salmon Flu & You: Myths and Mysteries

Salmon at the Ballard Locks (Photo: MvB)

The lethal and highly infectious salmon anemia virus (ISAV) has, it’s been reported by the New York Times, “detected for the first time in wild salmon in the Pacific Northwest.” The virulent form causes damage to blood vessels and blood cells–sick fish have pale gills and hemorrhage internally.

Of 48 juvenile sockeye salmon taken from British Columbia’s River Inlet, two tested positive for ISAV. Those findings are being checked now by third parties, but the original was performed by Dr. Fred Kibenge, from the OIE reference lab for ISAV. (Kibenge’s name is on most every ISAV study you will come across.)

Simon Fraser University’s Richard Routledge, a lead author on the study with biologist Alexandra Morton, is quoted as saying the virus might have “a devastating impact” on wild and farmed salmon. To date the virus has had its most lethal results in the hot zones created by salmon farms. Specifically, salmon farms raising Atlantic salmon.

A 2006 study found, “Coho salmon were resistant to all ISAV isolates”–Pacific salmon could carry the virus, but would not display symptoms. They were a disease reservoir. (This despite a 2001 study that found Chilean farmed Coho were killed by ISAV.) That’s why this finding, in a mysteriously declining population of Pacific salmon, is so disturbing.

Nor is the activist Morton disinterested, as her blog makes clear:

…Canada has failed to maintain a line of defense against ISAV. There is no place on the Fish Health Certificate that must be signed by foreign hatcheries to report ISAV. Even when the European strain of the virus began spreading in Chile, Canada did not close the border to eggs, government did not even make it a reportable disease if it occurred on a fish farm, even though it is an internationally reportable disease.

Classified as an Orthomyxoviridae virus, ISAV’s “behavior” is compared analogically to influenza, while researchers attempt to find out how, specifically, the virus works: “Through functional studies of the coded proteins it has been established that RNA segments 5 and 6 code for a fusion protein and hemagglutinin, respectively, while two polypeptides coded by segments 7 and 8 inhibit interferon induction.”Ah.

It’s definitely a fish flu, and not something you can pick from a can of salmon mousse (unless you are an Atlantic salmon), but of course influenza-type viruses tend to mutate. When scientists examined the 2007 strain of ISAV that decimated Chilean salmon farms, they discovered that the strain had arrived in Chile about 1996. The 2007 incidence of ISAV “caused the overall production of salmon to plummet 50% and 15,000 employees to lose their jobs.”

(ISAV is not the only disease stalking salmon, of course: “Severe infection by the myxozoan parasite Ceratomyxa shasta has, in large part, been responsible for the declining numbers of juvenile K[lamath] R[iver] fall Chinook and coho salmon and subsequent impacts on later adult returns.“)

U.S. Senators Maria Cantwell (D-WA), Lisa Murkowski (R-AK), and Mark Begich (D-AK) are taking no chances on it being ISAV. The three are calling for an investigation of the potential spread of the virus: Commerce, Justice, Science (CJS) Appropriations bill (H.R. 2112), “calls on the National Aquatic Animal Health Task Force to evaluate the risk the virus could have on salmon off West Coast waters and Alaskan waters, and to develop a plan to address this emerging threat,” says a release from Cantwell’s office.