Infectious salmon anaemia,
Canada
Information received on 19/12/2012 from Dr Brian Evans, Chief Food Safety Officer/Chief Veterinary Officer, Office of the President, Canadian Food Inspection Agency, OTTAWA, Canada
Summary
Report type Immediate notification
Date of start of the event 26/11/2012
Date of confirmation of the event 04/12/2012
Report date 18/12/2012
Date submitted to OIE 19/12/2012
Date event resolved 28/01/2016
Reason for notification New pathogen strain or disease manifestation
Manifestation of disease Clinical disease
Causal agent Infectious salmon anaemia virus
Nature of diagnosis Laboratory (advanced)
Related reports Immediate notification (18/12/2012)
Follow-up report No. 1 (08/02/2013)
Follow-up report No. 2 (28/01/2016)
New outbreaks (1)
Outbreak 1 Bay d’Espoir, Newfoundland
Date of start of the outbreak 26/11/2012
Outbreak status Continuing (or date resolved not provided)
Epidemiological unit Farm
Water type Salt water
Population type Farmed
Production system Semi-open
Affected animals
Species Morbidity Mortality Susceptible Cases Deaths Killed and disposed of Slaughtered
Atlantic Salmon (Salmo salar) (kg) 3 (scale 0 to 5) 3 (scale 0 to 5) 1161626 420000 420000 741626 0
Affected population Atlantic salmon, vaccinated against ISA, approximately 3.8 kg in size. Concurrent diseases are present (bacterial kidney disease and infestation with sea lice) so the case-specific mortality figure may represent an overestimate. Mortality rates appear to be declining. Water temperatures are also declining and are 2 degrees Celsius at the surface and 8 degrees Celsius at a depth of 15m. Update on 8 February 2013: The ISA-specific case fatality rate cannot be determined with any precision as concurrent diseases were present.
Summary of outbreaks Total outbreaks: 1
Total animals affected
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Atlantic Salmon (Salmo salar) (kg) 1161626 420000 420000 741626 0
Outbreak statistics
Species Apparent morbidity rate Apparent mortality rate Apparent case fatality rate Proportion susceptible animals lost*
Atlantic Salmon (Salmo salar) (kg) 36.16% 36.16% 100.00% 100.00%
*Removed from the susceptible population through death, destruction and/or slaughter
Epidemiology
Source of the outbreak(s) or origin of infection
  • Unknown or inconclusive
Epidemiological comments The identified strains have not been reported before. The population is infected with at least 2 strains of ISAV (non-HPR0); one is most similar to HPR6, the other does not demonstrate any particular similarity to any previously described HPR type. Both are considered to be North American as opposed to European strains. It is hypothesized that incursion into this farm may have originated from infected wild finfish. The next report will be submitted when fish are removed from the farm.
Control measures
Measures applied
  • Movement control inside the country
  • Quarantine
  • Traceability
  • Surveillance outside containment and/or protection zone
  • Official disposal of carcasses, by-products and waste
  • Surveillance within containment and/or protection zone
  • Vaccination permitted (if a vaccine exists)
  • No treatment of affected animals
Measures to be applied
  • Disinfection / Disinfestation
  • Modified stamping out
New pathogen strain or disease manifestation
Description of new strain The population is infected with at least 2 strains of ISAV (non-HPR0); one is most similar to HPR6, the other does not demonstrate any particular similarity to any previously described HPR type. Both are considered to be NA as opposed to European strains.
New Disease Manifestation
Diagnostic test results
Laboratory name and type Species Test Test date Result
Department of Fisheries and Oceans (DFO), Gulf Fisheries Centre (National laboratory) Atlantic salmon (Salmo salar) real-time reverse transcriptase/polymerase chain reaction (RRT-PCR) 17/12/2012 Positive
Department of Fisheries and Oceans (DFO), Gulf Fisheries Centre (National laboratory) Atlantic salmon (Salmo salar) reverse transcription - polymerase chain reaction (RT-PCR) 04/12/2012 Positive
Department of Fisheries and Oceans (DFO), Gulf Fisheries Centre (National laboratory) Atlantic salmon (Salmo salar) virus isolation 14/12/2012 Positive
Future Reporting
The event is continuing. Weekly follow-up reports will be submitted.
Map of outbreak locations