ASF BACKGROUNDER Atlantic Salmon Federation
P. O. Box 5200, St. Andrews, NB E5B 3S8
P. O. Box 807, Calais, ME USA 04619–0807
Tel: (506) 529–4581
www.asf.ca
Nov. 18, 2013
INFECTIOUS SALMON ANEMIA (ISA) – THE FACTS
General
• Infectious Salmon Anemia (ISA) is a virus that is highly contagious in the marine environment, spread through the water between Atlantic salmon within a grow-out site, and carried by the water from one site to another
• ISA is highly lethal to Atlantic salmon, but does not harm humans, according to all sources.
• ISA is complicated to diagnose, as there are both virulent and non-virulent forms of the virus. The virulent form occurs through mutation, possibly as the result of stress factors in the salmon. When a lab says
“suspected” of having ISA, in part they are determining if the virulent form of ISA is present.
• ISA was only discovered in wild Atlantic salmon in 1999, but has been known in farmed Atlantic salmon from a much earlier date
• ISA was unknown to science prior to epidemics in the Norwegian salmon farming industry in 1984
• Disease symptoms include the salmon becoming lethargic or moribund, lifting of scales, protuberance of the eyes, skin lesions, pale gills, and internal hemorrhages.
Geographical Distribution
• ISA is found on both sides of the Atlantic Ocean, and at times has caused massive losses for salmon farmers in Norway, Scotland, and the Faroes.
• Norwegian salmon farms were the first to be affected, and, by 1990, 101 salmon farms were infected
• In Scotland, an outbreak in 1998 spread so that, by the following year, 11 sites were infected, and a further 24 sites were suspected of being infected, a total of 10% of Scotland's salmon farms. Since then there have been outbreaks from time to time.
• In the Faroe Islands the aquaculture industry was nearly wiped out by ISA outbreaks from 2001 to 2003, resulting in losses to the industry of DKK 250 Million Canada and Maine
Recent History
• In 2013 ISA epidemics hit aquaculture operations in Jan. at Liverpool Bay, resulting in CFIA giving permission for Cooke Aquaculture to take the 240,000 potentially diseased salmon and process them at a plant in New Brunswick, the first time this has been allowed, and causing a national outcry. In June, 850,000 at Goblin Cove, farmed by Gray Aquaculture, were ordered to slaughter. This south coast Newfoundland site is within two miles of the migration route of smolt and returning salmon bound for the Conne River.
• In July 2013 ISA accelerated in the same area of Newfoundland, with the 21 cage Pass My Can site of 650,000 farmed salmon ordered destroyed, and 2 cages of a Cooke site at Manuel’s Arm (approx. 100,000 farmed salmon) ordered destroyed. Then 2 more cages at Mamuel’s Arm were ordered destroyed in November 2013. (See Appendix A)
• In 2012 ISA epidemics hit aquaculture operations in first Nova Scotia and then Newfoundland, totalling at least 1,090,000 farmed salmon.
• Nova Scotia - In Feb. and in April, epidemic ISA resulted in the forced slaughter of 12 cages of salmon, approximately 250,000 salmon in Shelburne. A separate incident in July resulted in the slaughter at the Coffin Island site in Liverpool Bay of 4 cages, with at least 40,000 salmon
• Newfoundland - On the south coast, the Butter Cove site was forced to slaughter 450,000 farmed salmon due to ISA in July 2012. In December 2012 Cooke Aquaculture was ordered to destroy 350,000 salmon at their Pot Harbour site. All of these sites bracket the wild Atlantic salmon corridor to and from the Conne River.
History of ISA Epidemics
ATLANTIC CANADA (1996 - 2013)
Slaughter of ISA Farmed Salmon
• Between 1996 and 1999, ~ 4.5 million fish were slaughtered at 65 sites in New Brunswick.
• In 2000, 9 farm sites were infected and 1.5 million fish slaughtered.
• In 2002, 16 sites were infected and 2.4 million fish were slaughtered.
• In 2003, the sites infected began to drop to 10 and 405,000 fish were slaughtered.
• In 2007 at least 528,000 fish were destroyed
• In 2012 four sites (2 NS & 2 NL) had ISA - 1.2 million fish destroyed -
• In 2013 (to Nov. 18) six sites (1 NS & 5 NL) had ISA - 2.8 millon fish slaughtered
• TOTAL FISH DESTROYED - MORE THAN 13.5 MILLION
Compensation
• 1996-1997: a combined federal and provincial total of $40.5 million was paid to the aquaculture industry following the first kill of salmon as a result of ISA detection.
• 1999: Federal government and provincial governments contributed a total of $25 million dollars under the terms of the Disaster Financial Assistance Arrangements.
• 2006: Following two years of ‘negotiations’ with the province, DFO finally contributed another $10 million to cover losses as a result of ISA.
• Thus by 2006 the total was $75.5 Million in compensation to growers
• 2007 - Compensation unknown - perhaps $7 Million (low estimate)
• 2012 & 2013 - Compensation in Newfoundland - $33,115,810 (see Appendix A), plus additional compensation for slaughter order of November, 2013 of about $10 Million. Compensation in Nova Scotia - approximately $10 Million
• TOTAL COMPENSATION - MORE THAN $130 MILLION, and likely reaching $135 Million
MAINE, USA (2001-2005)
• 2001 - 2.5 million fish destroyed
• 2002 & 2003 - 150,000 fish destroyed
• $5.8M compensation directly, and another $2.5M was paid out directly by USDA to clean up the sites.
• No outbreaks since 2005
Pacific Ocean
• Chile's aquaculture industry was partly destroyed by widespread outbreaks of ISA in the past several years, resulting in the deaths of 10's of millions of fish, and the loss of thousands of jobs in the industry.
Chile is now trying to rebuild on a healthier model, but outbreaks continue to occur.
• In British Columbia, there were reports of ISA showing up in wild and aquaculture salmon, but the tests have proven inconclusive at this point. There is great fear as to impact on wild salmon species in BC
ISA Transmission and the Environment
• ISA likely infects fish via the gills and possibly by ingestion
• ISA is shed in urine, feces, epidermal mucus, gonadal fluids, blood and through tissue wastes when farmed salmon are slaughtered and processed.
• ISA thrives in cold water temperatures (5-15 celcuis). It does not survive at temperatures exceeding mid 20s.
• ISA can be transmitted either through the water or by close contact between fish.
• Sealice might act as mechanical vectors. They may also increase the susceptibility of fish to infection by stressing the salmon
• Wild fish may act as carriers. Salmonids might be the natural reservoir of the ISA Virus
• It remains uncertain whether adult Atlantic salmon can transfer the virus to eggs within the adult, but some scientists believe the non-virulent form of the virus can be transmitted this way
• ISA normally occurs in the salmon’s marine life stage, and only rarely has been reported among young fish
• There appear to be two yearly peaks of the disease – early summer and winter
• ISA is highly contagious, and besides Atlantic salmon can affect economically important species that include cod, herring and mackeral.
Controlling ISA
• ISA being highly contagious, it is necessary to slaughter immediately all the fish in any site suspected of having the disease
• It requires two positives within a cage of salmon for the cage depopulation to be ordered.
• Bay-wide management with single year classes has been implemented to attempt to control the outbreak of ISA. Overall it is successful, but there are still outbreaks, and those will result in widespread death of farmed salmon
. Left foot in front of the other..........we can walk you through it if you would like.
