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Neutralizing risks instead of Stamping-Out
Harm KiezebrinkAssociate Research Fellow
Research Institute for Animal Welfare & Animal Husbandry
Friedrich Loeffler Institut Celle, Germany
© 2015 Applied Veterinary Technologies Europe AB
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• Contact between migratory birds and poultry• Wind-borne spreading between farms, via dust
and feathers• Absence of bio security protection at the farm
level• Contact between humans and infected birds
Pathways for transmission
© 2015 Applied Veterinary Technologies Europe AB
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• “Estimating the Per-Contact Probability of Infection by Highly Pathogenic Avian Influenza (H7N7) Virus during the 2003 Epidemic in The Netherlands” (2012)
• “Avian influenza transmission risks: Analysis of biosecurity measures and contact structure in Dutch poultry farming” (September 2012)
• “Modelling the Wind-Borne Spread of Highly Pathogenic Avian Influenza Virus between Farms” (February 2012)
• “Genetic Data Provide Evidence for Wind-Mediated Transmission of Highly Pathogenic Avian Influenza” (March 2013)
Wageningen University is leading in researchon spreading of avian Influenza transmission:
© 2014 Applied Veterinary Technologies Europe AB
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What happened in Hollandduring the outbreak of H7N7,
March 2003?• 270 million Euro direct costs
• 29 786 804 birds culled
• 1.134 farms• € 238.000/ farm; €
9,31/ bird 5.4%10.7%
72.8%
11.2%InfectedSus-pectedPre-ventiveWelfare
© 2015 Applied Veterinary Technologies Europe AB
85%
15%
Infected poultry species
ChickensTurkeysMixed poultry
© 2015 Applied Veterinary Technologies Europe AB
3%
97%
Infections under small farming (free range)
and hobby farming
Infected/suspected Preventive
© 2015 Applied Veterinary Technologies Europe AB
Infections under small farming (free range)
and hobby farming
23%
68%
9%
Infected farm type
ChickensTurkeysMixed poultry
© 2015 Applied Veterinary Technologies Europe AB
Infections under small farming (free range)
and hobby farming
79.2%12.0%8.7%
Type of farms infected during the H7N7 outbreak in Holland
Labor-intensive farms (Layers/parent stock)Labor-extensive farms (broiler/breeders)Turkey farms
© 2015 Applied Veterinary Technologies Europe AB
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All current culling techniques were developed during the outbreak in Holland without prior testing:
• Stable gassing with CO2 en CO
• Container gassing• Electrocution (waterbath method)
Because of its labor intensity, large-scale culling most likely contributed to the intensity of the outbreak Responders became spreaders of the virus: 50% of all responders showed antibodies and most likely became carrier of the virus
Large-scale culling contributed to the spreading
© 2015 Applied Veterinary Technologies Europe AB
Each farm type needs aspecific culling method
Labour intensive farms were culled using container gassing and electrocution Layers Biological farms (Grand)Parent stock Breeders Ducks Labour extensive farms were culled by stable gassing Turkeys Broilers Pullets
© 2015 Applied Veterinary Technologies Europe AB
All culling methods are extremely labour intensive
Poultry was caught or taken out of the cage by hand and carried out to the culling equipment outside the house
Large packages of gas bottles, containers, power generators, frond loaders etc., needed to be in place before the culling procedure could start
In case of stable gassing, large numbers of responders needed to enter the infected house and take out the carcasses and bring these to the disposal containers
© 2015 Applied Veterinary Technologies Europe AB
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Labour intensive farms are extremely vulnerable to get infected
• 4 727 124 of in total 29 370 427 birds were infected/suspected
• More than 79% of all farms with the notification Infected/suspected were labour intensive farms, indicating that poultry workers were most likely responsible for the infection of the flocks, due to the lack of following strict bio security protocols
• Only 12% of labour-extensive farms with young birds got infected, indicating that farms with a high-level of bio security and limited contact between humans and poultry are better protected against infections
• Only 3% of the small Free range and hobby farms got infected, indicating that direct contact between migratory birds and poultry plays only a marginal role
We do know that animal-to-human contact is the key transmitter of the infection
© 2014 Applied Veterinary Technologies Europe AB
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To summarize
1. Layer farms and turkey farms are extremely at risk
2. More than 79% of all farms with the notification Infected/suspected were labour intensive farms, indicating that poultry workers were most likely responsible for the infection of the flocks, due to the lack of following strict bio security protocols
3. Only 12% of labour-extensive farms with young birds got infected, indicating that farms with a high-level of bio security and limited contact between humans and poultry are better protected against infections
4. Only 3% of the small Free range and hobby farms got infected, indicating that direct contact between migratory birds and poultry plays only a marginal role
© 2014 Applied Veterinary Technologies Europe AB
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To summarize
5. Depopulation of broiler farms and hobby farms around infected layer farms turned out to be a destruction of resources
6. Complex culling methods are extremely costly
7. Stamping-out as a strategy is ineffective
8. Stamping-out caused distribution and spreading of the virus
© 2014 Applied Veterinary Technologies Europe AB
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What happened in Iowaduring AI outbreak in the USA
spring 2015?
© 2014 Applied Veterinary Technologies Europe AB
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Stamp it out!Within 24 hours:
Kill all animals Destruction all carcasses Clean and disinfect the establishments
© 2014 Applied Veterinary Technologies Europe AB
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Stamp it out! 71 farms were infected, of witch 35 caged
layer farms 33.1 million birds were killed, of witch 32
million layers were caged layers average layer farm-size is 913.000 layers Total costs in Iowa: 1 billion USD (total
costs USA 8 billion USD $ 27,4 million per layer farm/ $30 per
layer
© 2014 Applied Veterinary Technologies Europe AB
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Stamp it out! Approx. 1,000 to 1,500 workers involved
with Stamping- Out activities per farm Total costs in Iowa: 1 billion USD (total costs
USA 8 billion USD Loss of nearly 8,500 jobs Nearly $427 million in lost additional value,
more than half of which is income
Per layer farm, in average 1.188 tons of carcasses (average weight 1,3 kg/layer) were disposed
© 2014 Applied Veterinary Technologies Europe AB
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Complete failure of Stamping out strategy
Per September 18, 2015: Ventilation Shutdown method is allowed in the USA
Emergency response by the flip of a switch
Unprecedented financial Government support for the poultry industry
breach of OIE Terrestrial Code
Economic advantage for the US poultry industry on the international market
Total defeat for animal welfare friendly production
© 2015 Applied Veterinary Technologies Europe AB
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Concentrate on the different drivers• Introduction of the infection into the farm• Onward-spread between farms
• Transmission through contact structure between farms
• Wind-mediated spread • Transmission via rodents and farm dogs
Neutralize the risks of spreading• Isolate risks• Avoid direct contact• Avoid large scale operations
Emergency Response on a National level:Focus on epidemiology and the risks of spreading
© 2015 Applied Veterinary Technologies Europe AB
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• Seal off the area completely and isolate all who are living/working on the farm
• Reduce number of responders to an absolute minimum and if possible, use the farmers’ own labour force to depopulate the farm
• Prevent contact between responders and infected birds, carcasses and contaminated materials as much as possible
• Neutralize virus loads on carcasses before handling
• Avoid the use complex culling & disposal techniques
Focus on Neutralising infection/contamination risks
© 2015 Applied Veterinary Technologies Europe AB
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• Create a farm-based emergency response plan • Make an inventory of all possible transmission
routes• Possible introduction routes• Possible contamination risks• Possible routes for further spreading
• Use this plan as the basis for the farms’ bio security plan
• Define what would be the most appropriate culling & disposal technique
• Compensate and reward animal owners and farmers based on their active involvement
Emergency Response on local level:Focus on active involvement of animal owner and farmer
© 2014 Applied Veterinary Technologies Europe AB
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Neutralize risks instead of stamping-out