Published Date: 2001-04-17 23:50:00
Subject: PRO/AH/EDR> Infectious salmon anemia - Canada & USA (Maine)
Archive Number: 20010417.0763

INFECTIOUS SALMON ANEMIA ­ CANADA & USA (MAINE)
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See Also

2000
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Infectious salmon anemia - Faroe Islands 20000524.0819
1999
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Infectious salmon anemia - Canada (Nova Scotia) 19990531.0914
Infectious salmon anemia - UK (Scotland) 19990628.1093
Infectious salmon anemia - UK (Scotland) (02) 19990820.1442
Infect. salmon anemia - UK (Scotland) 19991108.2001
Infect. salmon anemia - USA (Maine), Canada (NB 19991022.1899
1998
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Infectious salmon anemia - UK (Scotland) 19980515.0944
Infectious salmon anemia - UK (Scotland) (04) 19981006.1979
Infectious salmon anemia - UK (Scotland): RFI 19980930.1940
Date: 17 Apr 2001
From: M. Cosgriff <mcosgriff@hotmail.com>
Source: Ottawa Citizen, 16 Apr 2001 [edited
< http://www.ottawacitizen.com/national/010416/5015193.html>

Salmon farmers in Maine knew there was a time bomb ticking in their waters;
last month, it exploded. Infectious salmon anemia (ISA), the virus ravaging
salmon aquaculture industry in Canada, Norway, and Scotland, has appeared
in 2 sea cage sites in Cobscook Bay near Eastport [Maine.
Fish farmers at the infected sites were forced to kill 50 000 salmon,
losing about a half a million dollars in the process. Since the virus
started killing fish in salmon farms off the coast of Norway 17 years ago,
ISA has been the foot-and-mouth disease (FMD) of the sea.
Fish farmers have slaughtered millions of salmon in an effort to control
the spread of the virus, a member of the flu family, which passes from fish
to fish in the water. The virus is not harmful to humans.
In salmon, it causes internal bleeding and destroys organs. The virus has
cost the salmon farming industry hundreds of millions of dollars worldwide
and continues to spread. In addition to this latest outbreak off the coast
of Maine, the wide-ranging virus has recently appeared in sea cages off the
coasts of Chile and among Denmark's Faroe Islands.
On the east coast of Canada, ISA has already cost fish farmers $70 million.
During the past 3 years, 4.5 million salmon have been killed in the Bay of
Fundy in an attempt to control the spread of the disease. The virus first
appeared in the Bay of Fundy in 1996 and had spread to cages as close as 10
km from the United States border. "The real surprise about this, is that it
took as long as it did for it to be detected across the border in Maine,"
says Fred Whoriskey, vice-president of research for the Atlantic Salmon
Federation, a wild-salmon conservation group based in St. Andrews, N.B.
Sebastian Belle, the executive director of the Maine Aquaculture
Association, says fish farmers in the state are preparing to do whatever it
takes to contain the disease. In recent years, Maine fish farmers have been
paying a special tax to the state government to fund a rigorous biosecurity
program employing an independent veterinarian to inspect all sea cages and
processing facilities.
Maine fish farmers have the advantage of having learned from the mistakes
of other countries that failed to control the virus before it reached
epidemic proportions. When fish started dying in sea cages in the Bay of
Fundy in 1996, it took scientists almost a year to identify the source of
the mysterious illness. By the time scientists confirmed the virus was a
variation of the Norwegian ISA, there was a full-blown epidemic in Canadian
waters.
Nelle Halse, a spokesperson for the New Brunswick Salmon Growers
Association, says the industry in the Bay of Fundy is starting to control
the spread of the disease and will help fish farmers in Maine deal with the
outbreak. "It's really a disease that has to be managed; it may never go
away," she says. "As soon as Maine knew they were into this, they were
talking to our fish health committee."
The Canadian fish farmers have been controlling the spread of the virus
through good husbandry -- killing all fish at an infected site and allowing
the waters to lie fallow to break the cycle of infection. When Canadian
salmon farmers receive a positive test for ISA, they kill first and ask
questions later, without waiting for fish to become sick. "It removes the
pathogens immediately," Ms. Halse says. "For us it was a real learning
experience."
While the federal and provincial governments have paid more than $20
million in compensation to Canadian farmers who killed their salmon because
of ISA, fish farmers recently established an industry-funded compensation
program. When farmers know there's compensation coming, they will act more
quickly to remove the virus from their site. [Having an indemnity plan is
crucial to the control of any disease requiring eradication of the host
animal. ­ Mod.TG
Federal Department of Fisheries and Oceans scientists are now testing a
vaccine for the virus, and preliminary results have been encouraging. The
number of infected sites in Canadian waters has been reduced during the
past 3 years from 40 in 1999, to 17 last year. So far this year there is
just one, although the industry is now entering the most dangerous period
for the emergence of the virus as the water warms.
However, the ISA story doesn't end at the sea cages. Scientists discovered
ISA in wild fish 2 years ago, a development that alarmed conservationists
of wild Atlantic salmon, who are desperately trying to protect a species
already on the road to extinction.
In 1999, Mr. Whoriskey detected the virus in both wild salmon and escaped
farmed fish in the Magaguadavic River in southern New Brunswick. The virus
was also found in wild brood stock Mr. Whoriskey had collected to help
restock the river. Instead of killing the infected brood stock, he bred
them to determine whether the disease was "vertically transmitted" to their
offspring. As soon as the eggs began hatching, the salmon fry tested
positive for the disease. Mr. Whoriskey ordered the fish be destroyed.
ISA has also been detected in wild fish in Scotland and the Shetland
Islands. In January, the Department of Fisheries and Oceans released a
troubling report suggesting salmon from the St. John River in New
Brunswick, the Morell River on Prince Edward Island, and the Margaree River
on Cape Breton had tested positive for the virus. However, Mr. Whoriskey
says questions are being raised about the testing methods in these rivers
and he remains hopeful these latest reports are "false positives."
Nevertheless, conservationists remain concerned about the interaction of
escaped-farmed salmon and wild salmon. Mr. Whoriskey has found that
escapees and wild fish are breeding on the Magaguadavic River, altering the
genetics of an endangered strain of fish.
Salmon regularly escape from sea cages. In December last year, 100 000
salmon escaped from a site in Machais Bay off the Maine coast during a
storm. There are few wild salmon left in Maine. The salmon in 8 Maine
rivers were added to the federal endangered species list last year. One of
these rivers, the Dennys, flows into Cobscook Bay, where the ISA outbreak
occurred.
"Obviously it doesn't help to have additional centers of the virus
particles that can infect wild fish in an area where populations are
depressed. There's still great concern about this disease, but also hope it
will be brought under control so it will pose a minimal risk to the wild
stocks," said Mr. Whoriskey.
Ms. Halse has been watching the news reports about the FMD livestock crisis
in Europe with a certain measure of sympathy and understanding. "It might
help people understand what it is all about," she says. "It is not about
carelessness and greed. This is the kind of stuff that happens on a farm.
It's about eradicating and killing off animals, and the losses are
devastating."
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