Transcript Slide 1

Infectious Salmon Anemia (ISA)
Development and application of a national contingency plan
for emergencies in aquaculture – Experience of a country
Michael David, MS, VMD, MPH
USDA APHIS Veterinary Services
Mazatlán, Mexico
November 11-12, 2008
Acknowledgements
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Dr. Gary Egrie – Aquaculture Specialist, APHIS/VS, Maryland
Dr. Steve Ellis – VMO, APHIS/VS, Maine
Ms. Teresa Robinson – Biologist, APHIS/VS, Maine
Other State and Industry
Maine
Isolated Broodstock
Lethal spawning
Collecting Eggs & Milt
Broodstock Sampling
Disinfection & Hardening
Egg trays
Hatchery Tanks
Hatch house
Smolt field
Smolt Transport
Smolt
Transfer
Harvesting
Infectious
Salmon
Anemia
Epidemiology
• Virus shed in body excretions (feces, urine, mucus)
• Transmission
– Ingestion of contaminated tissues/fluids
– Physical contact
– Sea lice
• If uncontrolled, it will spread from site to site
• Onset of clinical disease affected by:
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Length of time fish have been in saltwater
Water temp
Vx status
Sea lice (copepod) load
Nutrition
Immune system status
Site management procedures
Clinical signs
and Gross pathology
• lethargy
• protruding eyes
• pale gills
•severe anemia
• swelling of the spleen
• swelling and hemorrhaging in the
kidney and other organs
• darkening of the posterior gut
• fluid in the body cavity
Cobscook Bay: 2001 detection
•2001: detection of ISA and 1 M fish depopulated
•Jan 2002: ISA program implemented
•Feb 2002: 1.6 M add’l fish depop
•Completes depop in Cobscook Bay
Cleaning &
Disinfection
Management of outbreak
Outbreak and its response
• May 2002: restock sites
• May 2002 – May 2003: 13 months of negative monthly samples
• June 9 2003: Site - samples collected 1st cage
• June 12 2003: positive test results confirming ISAV infection (i.e. 2
fish by 2 tests in one cage)
• June 18 2003: completion of fish removal 1st cage
• June 25 2003: samples collected 2nd cage
• July 1 2003: positive test results confirming ISAV infection in 2nd
cage
• July 6 2003: completion of fish removal 2nd cage
4
Month & Year
Fe
b- 0
5
6
Oc
t-0
05
05
Ju
l-
Ap
r-
-04
De
c
-04
n-0
Se
p
Ju
r-0
4
-03
No
v
Ma
3
-03
y-0
Au
g
Ma
# of cages
ISA outbreak (2002-2006)
ISA Confirmed Cages 2002 - 2006
4
3
2
1
0
Timeline of ISA Confirmed Cages 2002 - 2006
First confirmed
ISA positive
cage of the
2002YC
First confirmed
ISA positive
cage of the
2003YC
First confirmed
ISA positive
cage of the
2004YC
No 2005YC fish
in Cobscook Bay
No ISA confirmed
cages in the
2006YC fish
# of cages
4
3
2
1
Spring 2002,
new smolts
stocked in
lower part of
bay
Spring 2003,
smolts
stocked in
upper part of
bay
March 2004,
all 2002YC
confirmed
sites out of
water
Spring 2004,
smolts
stocked in
lower part of
bay
August 2005,
all 2003YC
confirmed
sites out of
water
March
2006, all
2004YC
sites out of
water
ar
-0
6
M
De
c05
Se
p05
Ju
n05
ar
-0
5
M
De
c04
Se
p04
Ju
n04
ar
-0
4
M
De
c03
Se
p03
Ju
n03
0
2006YC - 13 month
fallow for
the sites in
ME & NB
Response and actions taken
• Increased sampling
frequency to weekly on
affected sites, biweekly on
other sites in the bay
• Collected viral samples
from fish in cages with a
previous PCR+ result
• Removed cages with
positive test results, whether
or not confirmed
Example of aggressive cage removal
• Positive PCR results Aug7, Aug11, Aug12 &
Aug15/2003
• No corroborating IFAT tests
• Clinical signs of disease observed
• Cage removed voluntarily on Aug22/2003
• Cage was confirmed positive on Sep12/2003 due
to positive results of viral samples taken Aug12 &
Aug15
• Three weeks less viral exposure to other cages
Chronology of events
• 1996: detected in New Brunswick, Canada
• 2001: first identified in Cobscook Bay, Maine
– Industry voluntarily depopulates affected sites
– Sites allowed to fallow for 3 months
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2002: May – new smolts stocked
2003: June – two cages positive at two sites
Sep 2003 – Feb 2006: 40 more cages positive
Mar 2006 – Apr 2006: USA-Canada coordinated fallowing
2006: May – new smolts stocked
– No infection/disease for more than 2 years
– Fish to be harvested Feb 2009
• 2009: Spring – new smolts to be stocked
Biosecurity
Biosecurity Practices
• Implement mandatory third-party biosecurity audits of
farms and vessels
• Have dedicated site-specific personnel, equipment &
vessels
• Disinfect all aquaculture equipment after use
• Disinfect crew and visitor gear before and after transport
to a site
• Disinfect mort divers between cages and at the end of
the dive
– Have dedicated site-specific gear for each diver and cagespecific dive bags
• Disinfect boat and mort tender gear at the end of each
dive
• Clean and disinfect vessels before being moved between
zones or across the border
Boot disinfection
on vessel
Iodophor scrub station
Disinfection after a dive
Disinfection of diver between cages
Management Practices
• Establish management zones
– 2006: new management zones established based on
hydrographic models of tidal exchange between sites on both
sides of the border
• Fallow all sites in a management zone for one to three
months
• Restrict movement of vessels, equipment and personnel
between sites and management zones
• Prohibit movement of fish between sites
• Selective age-grouping of fish by zone
• Monitor sea lice periodically
• Conduct monthly surveillance for ISAV
• Depopulate affected cages
Bay Management Zonation
From this…
… to this
Industry
Collaboration & Program
Harmonization
• Held regular meetings between USDA APHIS and
authorities from New Brunswick, Canada (starting
in 2003) to discuss infection status, program goals
and collaboration strategies.
– Also held meetings with state government officials,
industry managers and veterinarians.
• Visited sites, processing plants, and feed
companies
• Result of meetings:
– Improved ISA control efforts on both sides of the border.
– Improved communication, data-sharing and cooperation.
– Improved management strategies.
Infectious Salmon Anemia Program
• ISA was the first aquatic disease triggering
USDA/APHIS intervention
– Resulted in establishment of an aquatic health program
• Formed small committee to establish the ISA
Program Standards – (USDA, State, industry and
aquatic health professionals)
– Used Canadian policies and experience and Norwegian
epidemiologic findings as basis of ISA standards
• Shared resources
– Funding: USDA ISA emergency funding (December 2001)
• No appropriated funding
– Personnel: State partner, DMR, lease site and quarantine
authority, vessel movement control and enforcement
capabilities
Seven Components
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Surveillance
Testing
Disease reporting
Disease control and
biosecurity
• Quarantine
• Depopulation
• Partial compensation
Next steps …
•Common management practices
•Common biosecurity procedures
•Common database
•Health and production data
Muchas Gracias