Canada kept detection of salmon virus secret

By:  Craig Welch
Source: The Seattle Times

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.

Canadian officials never told the public or scientists in the United States about those tests — not even after evidence of the virus discovered in October was treated as an international emergency, according to documents and emails obtained by The Seattle Times.

The researcher's work surfaced only this week after she sought and was denied permission by a Canadian official to try to have her old data published in a scientific journal.

Scientists and wild-fish advocates long have feared the arrival of infectious salmon anemia (ISA) virus, a pathogen linked to aquaculture that has killed millions of farmed salmon in Europe and Chile. They say it could mutate and devastate wild fish stocks.

The virus never has been confirmed on the West Coast by follow-up tests, but word of the earlier research raises new questions about the Canadian agency charged with assessing the risk. Environmentalists in Canada and some U.S. politicians worry that Fisheries and Oceans Canada may be ill-equipped to deal aggressively with the risk because it's responsible both for protecting the country's wild fish and for promoting British Columbia's salmon farms.

U.S. scientists on Tuesday expressed dismay that the Canadians never had mentioned the researcher's work. The scientists also said they feared there had been little effort to conduct new tests to see whether she'd been right.

"We had no knowledge of any of this," said Jim Winton, a top fish virologist at the U.S. Geological Survey in Seattle, who reviewed the researcher's findings this week. "No one ever revealed that there was a publication that was ready to go to a journal or that the data were as compelling as they appear to be. This is puzzling and very frustrating. It's unfortunate that this information was not available sooner. This should have been followed up years ago."

Ted Meyers, Alaska's chief fish pathologist, agreed.

"If it were my lab," he said, "we would have looked a lot more thoroughly before we let 10 years pass. I have great respect for the scientists at Fisheries and Oceans, but I think sometimes the politicians get in the way."

Fisheries and Oceans Canada declined to answer questions Tuesday. It issued a brief statement acknowledging the researcher's work, but said the tests were in error. "Based on the best science available, it was concluded that her results had produced a false positive," the statement said.

But Winton and other scientists said the research appeared to be thorough. The type of genetic tests the Canadian scientist performed were unlikely to have produced all false positives, unless all samples were contaminated.

"The Canadian response is less than satisfactory," Winton said. "It seems inadequate to the occasion."

Why virus is a threat

While not harmful to humans, a virulent, highly contagious form of ISA linked to farmed Atlantic salmon has killed millions of fish in farms in Europe since 1984. Evidence suggests ISA then traveled from Norway to Chile on imported fish eggs, where it killed tens of millions more farmed Atlantic salmon in 2007 and 2008.

Scientists and wild-fish advocates worry that, if the virus gets into one of the 150 or so Atlantic-salmon farms that dot the British Columbia coast, it could fester among tightly packed fish, work its way into wild salmon and mutate into a new lethal form.

The virus is considered so dangerous that, if its presence is confirmed, Canada is obligated to report it to the World Organization for Animal Health, just as it would foot-and-mouth disease or bird flu. Such a report would be a devastating blow to British Columbia's aquaculture industry.

That's why some, such as Sen. Maria Cantwell, D-Wash., have encouraged Canadian officials to share information about the virus with U.S. scientists.

"We should not rely on another government — particularly one that may have a motive to misrepresent its findings — to determine how we assess the risk ISA may pose to American fishery jobs," Cantwell said this month.

This fall's fish scare erupted in October when a Simon Fraser University professor announced that a highly regarded independent laboratory had detected traces of the virus in two juvenile wild sockeye taken from Rivers Inlet in northern British Columbia. Independent follow-up tests proved inconclusive because the samples were so degraded.

Cantwell and Alaska's two senators pushed a measure through Congress to coordinate a salmon-testing and research plan.

But no one in the U.S. apparently knew those two fish weren't the first on the West Coast to test positive.

What researcher found

The first appear to have been found by Molly Kibenge.

In 2002, she was a visiting fellow in fish biology at a government lab on Vancouver Island. There, she took samples of wild chinook, coho, chum, sockeye and pink salmon from Southeast Alaska, the Bering Sea and the West Coast of Vancouver Island.

She found evidence of a European strain of the virus — but no illness — in 117 fish, according to a paper she prepared later. She concluded a nonlethal form of the virus may exist naturally in wild Pacific salmon. Her results went nowhere.

In the wake of the October virus report, she sought permission from her lab colleague, Simon Jones, who works for a division of Fisheries and Oceans Canada, to submit her old research to a journal.

"Your email is timely," Jones wrote back last month. "Recent events in BC concerning the alleged detection of ISA brought to mind the research you conducted ... and some of the questions it raised."

But Jones reminded her that his agency had disputed her results. He declined to give his permission.

Her husband, Fred Kibenge — a respected fish virologist who has led much of the world's ISA research and who performed the tests on the two British Columbia sockeye — wrote Jones back 10 days later. Kibenge said he still would share his wife's data with virus investigators to "clarify some of the issues."

The Kibenges declined to be interviewed. Jones referred calls to Fisheries and Oceans Canada.

But Winton and other U.S. scientists said Molly Kibenge's paper looked sound, and that research on the virus was notoriously hard to replicate. Her work suggested wild salmon may contain a natural variant of ISA — information that would have helped point to new avenues of research.

"It would have been nice to find out sooner," said Meyers, the Alaska fish pathologist. "I would have revisited that data in a heartbeat."

"It was certainly a surprise," said Bruce Stewart, with Northwest Indian Fisheries Commission, which is trying to help map out plans to test U.S. salmon for the virus. "I guess it's good that it came out now."

Cantwell agreed. "These troubling reports reinforce the need for a coordinated, multinational strategy to control the spread of this virus threat," she said in a statement. "American and Canadian scientists need to have access to all relevant research."

In fact, the three U.S. scientists agree that a fuller airing of Molly Kibenge's work may well have tempered initial fears this fall. Her research points away from the possibility that any ISA virus found in wild Pacific salmon likely started with farmed fish.

"Maybe we've got our own homegrown version of ISA right here," Meyers said.

And if Kibenge's work is verified, he said, the risk to wild fish may be far less than once thought.