experiences HPAI H7N7 2003 - 20110110
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Transcript experiences HPAI H7N7 2003 - 20110110
Workshop on emergencies and crises
EXPERIENCES WITH
H7N7 HPAI IN BELGIUM
Giza, 17-18 January 2011
Philippe Houdart
crisis prevention and management unit
FASFC
Belgian Federal Agency for the Safety of the Food Chain
Contents
Belgian poultry industry
Chronology HPAI outbreak 2003
Control strategy
Critical points in control strategy
Costs & compensation
Conclusions
Belgian poultry industry in 2003
farms
breeders
poultry
200
2.600.000
70
900.000
520
12.000.000
65
1.700.000
broilers
1.100
28.000.000
turkeys
50
500.000
2.005
45.700.000
breeder pullets
layers
layer pullets
total
Belgian 2003 poultry production
hatching eggs
table eggs
broilers
360.000.000
3.300.000.000
165.000.000
Geographical distribution of poultry farms
vol_oxc_coord
Rues
Routes_secondaires
Autoroutes
Nationales
Hydro
Zones_industrielles
Fôrets
Zones_habitées
What happened in 2003
28 Feb: outbreak of H7N7 in Gelderse Vallei (The Netherlands) 85 km
from Belgian border
5 Apr: outbreak in province of Dutch Limburg 15 km from Belgian border
11 Apr: outbreak less than 7 km from Belgian border
16 Apr: first outbreak in Belgium (province of Limburg)
20-28 Apr: 7 more outbreaks in Belgium (provinces of Limburg/Antwerp)
12 Jun: lifting of measures except for restocking areas
15 Jul: final lifting of measures and restocking
28 Feb
outbreak in The Netherlands
(Gelderse Vallei) at 85 km
from Belgian border
= poultry dense area
Netherlands
Germany
Belgium
in Belgium:
control of imported poultry
and hatching eggs
France
biosecurity measures
on all poultry premises
Luxemburg
import from Netherlands is
suspended
epizootic cannot be controlled
spreads southwards in
following weeks
5 Apr
first outbreak in Dutch
province of Limburg at 15 km
from Belgian border
Netherlands
delimitation of buffer zone
in Belgian province of
Limburg (20 km x 20 km)
Belgium
France
Germany
Luxemburg
control of transport of live
poultry:
- only transport to
slaughterhouse allowed
- no restocking of empty
premises
stricter biosecurity
measures
11 Apr – 14 Apr
Netherlands
prov. of Limburg
outbreaks in Dutch province
of Limburg at less than 7 km
from Belgian border
delimitation of surveillance
zones within buffer zone in
Belgian province of Limburg
measures in surveillance
zone = Directive 1992/40/EC:
- transport ban for poultry
and poultry products
- biosecurity measures
- identification of premises
at risk
measures in buffer zone
remain unchanged
16 Apr
Netherlands
first Belgian outbreak at
approx. 15 km from border,
within existing BZ
delimitation of protection
zone (3 km) and surveillance
zone (10 km)
culling of poultry at risk
measures = Directive
1992/40/EC:
prov. of Limburg
measures in reduced
buffer zone unchanged
nationwide standstill for
poultry and hatching eggs
20-28 Apr
7 more outbreaks in provinces of Antwerp and Limburg
situated within and outside existing buffer zone
delimitation of protection zone (3 km) and surveillance zone (10 km) around
each outbreak with merging of several zones
delimitation of buffer zone around outbreaks in province of Antwerp
culling of all poultry in protection zone
measures in zones = Directive 1992/40/EC
measures in buffer zones remain unchanged
nationwide standstill for poultry and hatching eggs is maintained with exception
of direct transport of slaughter poultry originating from outside areas at risk
to slaughterhouse
additional protection and surveillance zone in north of province of Limburg within
existing buffer zone due to outbreak in The Netherlands at less than 1 km from
border
28 Apr – 25 May
Netherlands
Belgium
26 May – 12 Jun
Netherlands
Belgium
12 Jun – 15 Jul
Netherlands
Belgium
Control strategy
in last decade Belgium has only been confronted with outbreaks of CSF
no experience with AI nor ND (obligatory vaccination programme)
invent specific control strategie along with developments in the field
based upon:
- European legislation (council Directive 1992/40/EC + specific Decisions)
- experiences gained in Netherlands since beginning of outbreaks
!!!! very infectious, fast spreading, hard to control disease !!!!
with unknown/unclear means of spread
Critical points in control strategy
diagnosis:
virus isolation test (embryonated eggs)
= official confirmatory test
slow proces
technically difficult
tissue culture test
RT-PCR test
fast, easy, large scale
as reliable as VI test
since time is critical
!!!! action (zoning, culling, …) is undertaken on basis of RT-PCR - tissue culture test !!!!
VI test is only used to confirm results afterwards
delimitation of zones:
- protection zone (3km)
- surveillance zone (10km)
legally defined zones
buffer zone (approx. 20km)
- additional safety net in between
contaminated areas and rest of the
country
- very flexible (not legally defined)
within each zone: movement/transport ban or restrictions (in accordance with risk) for
- poultry
- poultry products
- other farm animals, especially when housed on mixed farm with poultry
- possibly contaminated products/vehicles/persons (milk collection, feed, technical
contacts)
basis idea = empty zone as quickly as possible without restocking !!
nationwide transport ban:
- imposed by European Commission after 1st outbreak
- only transport of slaughter poultry directly to slaughterhouse (1-1) is allowed
- no restocking, nor transport of hatching eggs allowed
- maintained from 16 Apr – 5 May
+
+
very effective in preventing unwanted and uncontrollable contacts
between poultry holdings
natural emptying of broiler sector, less of laying sector
- very demanding on poultry sector:
- transport ban for hetching eggs = hatcheries empty for additional 3
weeks
- half of May: 80% of broiler farms empty
culling around outbreak:
how much is needed?
(risk assessment)
how much can you do?
100.000-150.000 head a day
infected poultry
suspected of being infected (direct contacts)
suspected of being contaminated (neighbouring poultry)
real preventive killing (to decrease population and reduce virus spread)
?
strategy:
- commercial farms: 10 km in Limburg (neighbouring outbreaks in Netherlands)
3 km in Antwerp (probably less virus spread)
- backyard poultry: 1 km
has to be completed within 10 days
200.000-250.000 head a day
solution = additional culling capacity generated with help of external private partners:
FASFC teams
+
CO gasing method (2-3 vol%)
+ whole stable at once
quick
not much high tech material needed
- CO gas is not as common as CO2
danger of explosion
cannot be used if stable is not airtight
- outbreaks
- suspected of being infected
- broiler farms
housed on
- parental farms
the ground
external teams
electrocution method
CO2 gasing method
mobile
containers
+ can be used in any stable
safe
CO2 is very common
- specialised equipment
much manual labor
- less risky farms
- layer farms
housed in cages
good interaction and good supplement of potential and means
cleaning and disinfection procedure prior to restocking:
problem = high infectivity and long viability of influenza virus in manure
Netherlands & Belgium
= densily populated area
specific procedure developed
by belgian and dutch veterinary
services
Italy
= less densely populated
solution based on:
- long period of disuse of stable
- stocking of manure on premise
Decision 2003/428/EC of 11 Jun 2003
- specific and detailed instructions regarding removal of contaminated material
- sentinel poultry on infected premises
cleaning and disinfection procedure prior to restocking = procedure in 8 steps
1. removal of manure, feed and other infected material
incinerated (outbreaks) or composted (other farms)
done by holder
3. wet cleaning of stable under high pressure
4. control of cleaning with ATP-test
(aminotrypsinephosphate)
done by FASFC
5. disinfection by specialised firm
minimal 21 days
2. dry cleaning of stables and premise
6. control of disinfection with hygienogramme
done by FASFC
at 2% of normal capacity
free ranging within whole stable
tested beforehand
layer pullets
8. follow up and testing afterwards of sentinels (outbreaks)
21 days
7. restocking with sentinel birds (outbreaks)
protection of field workers
problem = influenza virus is zoonosis
only became clear after 20 Apr (between 1st and following outbreaks)
specific protection measures for field workers and farmers of affected holdings
- vaccination with human influenza virus anti-reassorting with human strain
- intake of antiviral drugs (Tamiflu) anti-bird flu
only one case of mild
conjunctivitis observed
more than 80 cases
in Netherlands, including
one unfortunate death
(mostly prior to 20 Apr)
Compensation for farmers (€)
number
culled poultry
destroyed eggs
backyard poultry
destroyed feed
cost
4.412.000
6.314.425
3.200
1.414.500
5.713.000
447.000
6.000
303.000
7.500
13.896.000
3.000
3.619.000
170.000
51.000
total compensation
10.142.000
unused litter
destroyed one day old chicks
destroyed hatching eggs
compensation foreseen for loss of value of
heat treated hatching eggs
11.567.000
1.500.000
Main operational costs (€)
cost
4.704.000
1.143.000
74.000
1.136.000
203.000
killing
destruction of carcasses
destruction of eggs
cleaning and desinfection
destruction of feedingstuffs
destruction and compensation of
equipment
incineration of manure
221.000
300.000
total
7.781.000
Conclusions
very infectious, fast spreading disease, hard to control in densily populated areas
speed is essential
1. good preparation
- organizational level (structure)
- contingency manual plan and manual
- means and logistics (culling capacity,
laboratory capacity)
2. action must be taken swiftly
even before official confirmation of disease
3. buffer zone
is flexible and effective weapon
4. protection of field workers is important
THANK YOU
FOR YOUR ATTENTION