Dossier Piglets: German TV Report creats pressure regarding killing piglets on farms

Killing piglets on the farm remains a hot issue in Europe, demanding new methods. On January 12, 2016, the program of ARD Report (German National TV) broadcasted second program on the current method of killing piglets on the farm.

This program was the follow-up of the first Report program, published in June 2015, showing the embarrassed German Agricultural Minister. He explained that after the first Report program, the German politic forced the responsible German veterinary authorities to develop new techniques to introduce new methods that prevent unnecessary stress or pain during the stunning and killing , but according to this new footage, nothing has changed: the animals are still stunned by brute force and there is no control if the piglets are stunned before their throats are cut.

To change this situation, a team of specialists of the Friedrich Loeffler Institute in Celle/Germany, AVT Applied Veterinary Technologies – Innovation & Services (Germany) and Anoxia Europe (Holland) are working on legalizing the Anoxia method for this purpose.

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Ventilation Shutdown

Who takes the responsibility to flip the switch?

On September 18, 2015 the USA Government and the American egg producers announced that they would accept the Ventilation shutdown method as a method of mass destruction of poultry when other options, notably water-based foam and CO2, are not available for culling at the farm within 24-36 hours. This is actually the case on all caged layer farms in the USA, in particular in Iowa.

The Ventilation shutdown method consists of stopping ventilation, cutting off drinking water supply, and turning on heaters to raise the temperature in the poultry house to a level between 38 Celsius and 50 Celsius. Birds die of heat stress and by lack of oxygen in a process that easily takes over after a period of at least 3 days. Ventilation shutdown is a killing method without prior stunning of the birds, and as such is contrary to all international Animal Welfare standards.

Animal welfare specialists in disease control strongly oppose this introduction of the cruelest method of killing poultry that lost their economic value. The Humane Society (HSUS) described it as the “inhumane mass baking of live chickens”. With adequate preparation the alternative methods, like the water-based Anoxia foam method, can be available at each farm for immediate use in case of an outbreak. The ban of the Ventilation shutdown method should therefore be maintained and the Anoxia method should be further developed so that is suitable for application to caged layers and turkeys. In Germany, such a system is currently under development and will become commercially available soon.

The poultry industry in the USA ignores this development and asks for a formal approval of the Ventilation Shutdown method. Speaking on August 19, 2015, during the United Egg Producers (UEP) national briefing webinar, UEP President Chad Gregory explained that much research is being done concerning the feasibility of such a depopulation program.

“The government, the producers, the states and UEP, we all recognize that depopulation is going to have to happen faster and ideally within 24 hours.”

Quick depopulation of affected flocks is important, Gregory said, because the sooner a flock is depopulated, the risk of the virus going into fans and out into the atmosphere becomes smaller. Gregory said ventilation shutdown – if approved – would probably only be used in a worst-case scenario or when all other euthanasia options have been exhausted. Gregory did not elaborate on how to adequately prevent outbreaks and how to promote more animal-friendly methods.

The latest draft of the USDA Foreign Animal Disease Preparation Plan was published on August 25, 2015, and the publication of the Ventilation Shutdown Evidence & Policy on September 18, 2015, effectively created facts on the ground. This was done in a unilateral way, without any political consultation, without informing trade partners, and without a fundamental discussion whether or not the Ventilation Shutdown method should be made acceptable at all.

From a strategic point of view, the US poultry industry created an unprecedented commercial advantage for itself. Their competitors in Europe are responsible for biosecurity and for prevention of risks of infection, based on EU legislation. Each country has to implement a National Emergency Response plan based on Directive EC 1099/2009.
In Germany, public private partnerships called “Tierseuchenkasse” are responsible for the preparation of emergency response to outbreaks like HPAI, and work on an insurance model. The German government, the EU and the industry collectively carry the costs for emergency response activities.

TTIP

This is not the case in the USA. There, USDA APHIS is responsible for response activities and the taxpayer is paying the costs. This is a significant advantage over European producers, and with the TTIP ‘free trade’ negotiations in their final stage, the European poultry industry will be confronted with a significant distortion of trading conditions by this abandonment of animal welfare as a boundary condition in culling operations in the USA.

US egg producers are actively creating facts that will be very difficult to undo, and with the Ventilation Shutdown Method officially accepted by USDA Aphis, the industry effectively avoids to take its responsibility for risks inherent to the type of production with 31.000.000 caged layers, packed on 35 farms, and caged layer farms with an average size of 913.000 caged layers per farm. The consequences will be devastating: all Asian producers, who routinely use cage systems to produce eggs, will follow the example of the USA, just to be able to compete with the American poultry industry.

For the producers within the EU, it will even more difficult to compete with the US poultry producers. The ventilation shutdown method will on the mid- and long term destroy cage free egg production policy in Europe, putting the EU egg production methods as demanded by the European consumers at risk. In case the European industry would not able to produce against compatible prices, the consumers will become completely dependent on eggs produced outside the EU. As the situation is now, TTIP will not allow for mandatory labeling of animal welfare on eggs, so that EU consumers only will have the price as their decision criterion.

Senator Ron Johnson calls emergency response an economic issue; the Foreign Animal Disease Preparedness & Response Plan puts the limit for Stamping-Out on 24 hours; official guidelines introduce the Ventilation Shutdown method as a legitimate culling method in situations described as “where all other euthanasia options have been exhausted’ – the Ventilation Shutdown method in the USA is a fact with disastrous consequences for animal welfare and a new obstacle to TTIP.

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Dossier H5N2: killing poultry – without stunning! – by creating heat stress and suffication

The USA Government and industry groups seek ways to expedite depopulation of flocks affected by avian influenza when other options are exhausted.This would be against all International Animal Welfare standards, to kill poultry without prior stunning, by shutting down all ventilation and putting heaters to raise the temperature to a level that poultry would be killed by heat stress and lack of oxygen. Animal welfare specialists in disease control strongly oppose against the introduction of the most cruel method of killing poultry that lost their economic value and need to be culled, as if there would not be alternative methods available, like the Anoxia method. The ban of Ventilation shutdown method should therefore be maintained and the Anoxia method should b further developed so that is suitable for applying to caged layers and turkeys. In Germany, such system is currently under development and will be commercially available this Autumn.

The poultry industry in the USA is not aware of this development and pledges for the formal approval of the Ventilation Shutdown method as a form of emergency depopulation of flocks that have been affected by highly pathogenic avian influenza. Speaking August 19 during the United Egg Producers (UEP) national briefing webinar, UEP President Chad Gregory explained that much research is being done concerning the feasibility of such a depopulation program.

“The government, the producers, the states and UEP, we all recognize that depopulation is going to have to happen faster and ideally within 24 hours,” said Gregory. Quick depopulation of affected flocks is important, Gregory said, because the sooner a flock is depopulated, the risk of the virus going into fans and out into the atmosphere becomes smaller. Gregory said ventilation shutdown – if approved – would probably only be used in a worst-case scenario or when all other euthanasia options have been exhausted.

UEP’s animal welfare scientific committee, the American Association of Avian Pathologists (AAAP), and other organizations have visited with the USDA Animal and Plant Health Inspection Service (APHIS) about the issue, but Gregory said much research still needs to be done, taking into account factors such as temperatures, if any supplemental gas should be used, and how long it would take for the birds to die.

“These things all need to be researched and researched fast so that if [avian influenza] does come in the next couple of months, we can actually employ the emergency depopulation method by ventilation shutdown if it is the option that’s chosen with the government,” said Gregory. “A lot more needs to be done.”

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FLI Seminar on different response strategies: Stamping out or Neutralization

During this spring, American poultry producers lost birds by the millions, due to the High Pathogenic Avian Influenza outbreaks on factory farms. USDA APHIS applied the stamping out strategy in an attempt to prevent the flu from spreading.
With stamping out as the highest priority of the response strategy, large numbers of responders are involved. With in average almost 1 million caged layers per farm in Iowa, there is hardly any room for a proper bio security training for these responders. And existing culling techniques had insufficient capacity, the authorities had to decide to apply drastic techniques like macerating live birds in order to take away the source of virus reproduction.

This strategy didn’t work; on the contrary. Instead of slowing down the spreading of the virus, the outbreaks continue to reoccur and have caused death and destruction in 15 USA states, killing almost 50 million birds on mote than 220infected commercial poultry farms, all within a very small time frame.

The question is whether the priority of the response strategy should be on neutralizing the transmission routes instead of on stamping out infections after they occur. All indicators currently point out into the direction that the industry should prioritize on environmental drivers: the connection between outbreaks and wild ducks; wind-mediated transmission; pre-contact probability; on-farm bio security; transmission via rodents etc.

Once the contribution of each transmission route has been determined, a revolutionary new response strategy can be developed based on the principle of neutralizing transmission routes. Neutralizing risks means that fully new techniques need to be developed, based on culling the animals without human – to – animal contact; integrating detergent application into the culling operations; combining culling & disposal into one activity. This new response strategy will be the main subject of the FLI Animal Welfare and Disease Control Seminar, organized at September 23, 2015 in Celle, Germany.

This international – English-language based – seminar is open for animal welfare specialists, veterinary specialists, and emergency response experts. The event takes place on the premises of FLI; starts at 9 AM; and closes at 4 PM, after the general discussion. In case you need more information or any assistance, please contact me on: 0046 761 731 779 or by mail on harm.kie@gmail.com.
You are very welcome to pass this invitation to all of your colleagues, who may also be interested in the seminar.  

Transmission routes
The routes of virus transmission risks can be split into three categories:

1. Introduction of the infection into the farm
2. Onward-spread between farms
3. Spreading during outbreaks

Introduction into the farm entails the target farm’s exposure through incoming contacts (human and fomite), through inputs such as feed and egg trays and through neighborhood-related risks such as air-borne contamination. Onward spreading and spreading during outbreaks can be through farm outputs (waste and non-waste), outgoing contacts (human and fomite) and contamination of the neighborhood (e.g., through emissions from the farm). Therefore, all day-to-day farm activities involving people and/or materials and/or equipment going in or out of the farm must be systematically analyzed.

Category 1: Introduction of the infection into the farm
During the last HPAI H5N8 epidemic in the Netherlands (2014), a total of 5 traditional poultry became infected by separate introductions, from outside the building to inside and in contact with the birds. The risk of introducing the virus to a farm can be determined from the farm’s neighborhood characteristics, its contact structure and its biosecurity practices .
Neighborhood characteristics include factors such as the presence of water bodies (accessed by wild birds), the density of poultry farms (together with the number and type of birds on these farms) and poultry-related businesses and the road network. The use of manure in the farm’s vicinity is also deemed to be risky.

In nature, disease-causing strains of avian influenza rarely spread far because the birds sicken and die before they can fly to spread it to others. However, in unnatural, intensive agricultural systems, pathogens are more easily able to evolve from mild strains to dangerous, highly pathogenic forms.

Category 2: Onward-spread between farms

In Iowa, cage layer housing conditions (confining in average more than 100,000 animals each) may have an effect on immunity, but there is no such thing as being more or less susceptible to avian influenza virus infection; poultry in outdoor facilities that have more opportunities to engage in natural behavior are not more resistant to AI infection.
Probably the housing conditions themselves (windowless sheds, intensely overcrowded, unsanitary, with stressful living conditions for the birds) make exposure to AI virus easier. In the Netherlands it has been shown that. layer farms with outdoor facilities and therefore more and better contact with wild water birds have a much higher probability of introduction of AI virus than traditional indoor layer farms (which do not have windowless sheds).

Nine out of 10 chickens used for egg production in the U.S. are confined in barren wire cages. Due to the extreme confinement, hens —highly intelligent and social animals — cannot engage in natural behaviors. High levels of stress can lead to weakened immunity, rendering animals much more susceptible to disease. This makes the average caged layer farm in Iowa a plausible hotbed for outbreaks of avian flu.
Still, it is unlikely that the confinement of hens in cages is the only explanation for the current outbreaks in the U.S, especially in Iowa. The industrial indoor housing in remote locations with large distances between farm locations has always been considered as the perfect protection against introduction of viruses to the farm. Considering the current pace of outbreaks over large areas, other factors might have caused the transmission between farms, like:

a) Transmission through contact structure between farms
b) Wind-mediated spread
c) Transmission via rodents and farm dogs


a) Transmission through contact structure between farms

Contacts between people, equipment and vehicles prior and during outbreak situations are critical to determine the possible source of infection of a farm . Hired laborers are known to play a big role in interconnecting farms.
The farm’s exposure through incoming contacts (human and fomite), through inputs such as feed and egg trays and through neighborhood-related risks such as air-borne contamination. The latter can be through farm outputs (waste and non-waste), outgoing contacts (human and fomite) and contamination of the neighborhood (e.g., through water- or airborne emissions from the farm).

b) Wind-mediated spread
In the study, published in 2012 by Rolf Ypma et al, a comparison between the transmission risk pattern predicted by the model and the pattern observed during the 2003 Netherlands epidemic reveals that the wind-borne route alone is insufficient to explain the observations although it could contribute substantially to the spread over short distance ranges, for example, explaining 24% of the transmission over distances up to 25 km.

c) Rodents, scavengers and farm dogs
Besides a study published in 2007 Taiwan, little research has been undertaken into the transmission routes via rodents, scavengers and farm dogs. There are strong indicators for the assumption that rodents, scavengers and farm dogs could play a role in distributing and reintroducing HPAI.

Recently Avian Influenza was found in a farm dog in South Korea. The dog had antigens for the highly pathogenic H5N8.
Since the first case of a dog being infected with the poultry virus in March 2014, there have been 55 dogs found with antibodies to the bird flu virus. This is the first time bird flu has been found in a dog in Korea through the detection of antigens.

Category 3: Spreading during outbreaks
The impact of the outbreak of the Avian Flu Epidemic outbreak in the Netherlands in 2003 shows that biosecurity during outbreaks is one of the main issues to address. An estimated 1.000 people, possibly more have been shown to carry antibodies to the H7N7 virus active at that time.

Although the risk of transmission of these viruses to humans was initially thought to be low, an outbreak investigation was launched to assess the extent of transmission of influenza A virus subtype H7N7 from chickens to humans.

Most H7 cases were detected in the cullers. The attack rate (proportion of persons at risk that developed symptoms) of conjunctivitis was highest in veterinarians, and both cullers and veterinarians had the highest estimated attack rate of confirmed A/H7N7 infections.
From all people that had been questioned, 453 people had health complaints—349 reported conjunctivitis, 90 had influenza-like illness, and 67 had other complaints. We detected A/H7 in conjunctival samples from 78 (26·4%) people with conjunctivitis only, in five (9·4%) with influenza-like illness and conjunctivitis, in two (5·4%) with influenza-like illness only, and in four (6%) who reported other symptoms.
Most positive samples had been collected within 5 days of symptom onset.

A/H7 infection was confirmed in three contacts (of 83 tested), one of whom developed influenza-like illness. In three of these exposed contacts an A/H7N7 infection was confirmed. All three were household contacts. The first contact was the 13-year-old daughter of a poultry worker, who developed conjunctivitis approximately 10 days after onset of symptoms in her father. Six people had influenza A/H3N2 infection.

FLI Seminar
During the FLI Animal Welfare and Disease Control Seminar, organized at September 23, 2015 in Celle, Germany, a group of international experts will give their vision on how the possible contribution of each transmission route could be determined and how a revolutionary new response strategy could be developed, based on the principle of neutralizing transmission routes.

A selection of key experts in their field will be presenting their vision, like:

• Dr. Michael Marahrens, host of the event, presenting the theme of the day: Animal disease control in Germany: past – present – future
• Dr. Marien Gerritzen (Wageningen UR) who will discuss Welfare aspects of methods for emergency killing of poultry during disease outbreaks
• Dr. F. J. Conraths (Institute of Epidemiology, FLI, Greifswald – Insel Riems) who will present the role of wild birds in the transmission of influenza virus infections to poultry
• Dr. Guus Koch (Wageningen UR), explaining the virus sequence network of an avian influenza epidemic reveals virus adaptation and unexpected trans-mission chains
• Dr. Elbers (Wageningen UR), presenting the virus transmission during the out-break in the Netherlands, 2003
• Dr. J. Harlizius (Chamber of Agriculture North Rhine – Westphalia), discussing Lessons learnt from the outbreak of classical swine fever in Germany, 2006
• Dr. A. vom Schloß (North Rhine – Westphalia Animal Diseases Fund), discussing the reorganization of the provisions for animal disease control in Germany
• Dr. I. Schwarzlose (Institute of Animal Welfare and Animal Husbandry, FLI, Celle), explaining Animal Welfare during disease outbreaks and control measures in the context of European and German legal framework
• Mr. W. Hung (Environment & Animal Society of Taiwan (EAST), explaining the relevance of OIE guidelines during the HPAI outbreak in Taiwan.
• AVT participates in the seminar, discussing how to implement animal welfare in Standard Operating Procedures during culling of animals.
You are more than welcome to participate in this English-spoken event. You can sign up by replying your name, including the name of your institute/company, to angelika.gaupp@fli.bund.de, or by fax: +49/5141-3846-117.

We wanted this seminar to be accessible for all, and for that reason, the participation fee is € 70 only. Unfortunately, the number of participants is limited, so in case you’re interested, please let us know and respond before August 31, 2015. After you signed up, you will receive your detailed payment instructions.

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Animal Welfare & Disease Control Seminar Sept 23, 2015: Introduction of Avian Influenza into the industry

During the FLI Animal Welfare and Disease Control Seminar, organized at September 23, 2015 in Celle, Germany, a group of experts will give their vision on how the possible contribution of each transmission route could be determined and how a revolutionary new response strategy could be developed, based on the principle of neutralizing transmission routes.

There are several factors, which contribute to the unique presentation of an avian influenza outbreak, like the relationship of this virus with wild waterfowl. The virus is highly pathogenic for chickens and turkeys but not pathogenic for waterfowl.
Since the virus in our current outbreak is not pathogenic for waterfowl, the vast flocks of healthy virus-infected migratory geese and ducks travel thousands of miles, entering into commercial poultry-producing regions while shedding tremendous quantities of infectious avian influenza virus in their feces.
You are more than welcome to participate in this English-spoken event. You can sign up by replying your name, including the name of your institute/company, to angelika.gaupp@fli.bund.de, or by fax: +49/5141-3846-117.

We wanted this seminar to be accessible for all, and for that reason, the participation fee is € 70 only. Unfortunately, the number of participants is limited, so in case you’re interested, please let us know and respond before August 31, 2015. After you signed up, you will receive your detailed payment instructions.

This international – English-language based – seminar is open for animal welfare specialists, veterinary specialists, and emergency response experts. The event takes place on the premises of FLI; starts at 9 AM; and closes at 4 PM, after the general discussion.

In case you need more information or any assistance, please contact me on: 0046 761 731 779 or by mail on harm.kie@gmail.com.

You are very welcome to pass this invitation to all of your colleagues, who may also be interested in the seminar.

I am looking forward to see you there.

Kind regards,
Harm Kiezebrink

Associate Research Fellow FLI

Federal Research Institute for Animal Health
Friedrich Loeffler Institute
Dörnbergstr. 25/27 | 29223 Celle
Tel: +49 5141 3846 130 | Fax: +49 5141 3846 117
http://www.fli.bund.de/

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Dossier AI: Clean-up costs for avian influenza outbreak estimated to top £10 per bird


Clean-up costs could run to as much as £10 per bird for egg producers whose layer units are hit by avian influenza.

 

An outbreak of bird flu at Staveleys Eggs near Preston in Lancashire has, once again, highlighted the devastation the disease can cause. Nearly 200,000 laying birds have been culled following confirmation of avian influenza, and strict restrictions have been put in place around the farm and the surrounding area in an attempt to prevent the virus spreading to other nearby poultry units.

The Staveleys are likely to face a huge bill to get this farm up and running again following the outbreak, although no official figures appear to exist to illustrate the likely cost of a post-bird flu clean-up operation on an egg production unit. The Ranger has spoken to a number of people with some knowledge of the clean-up process and the regulatory system in an attempt to gauge the likely financial impact of cleaning an infected site.

“Even on the smallest site, I would be very surprised if you got away with £100,000,” said Julian Sparrey of Livetec Systems. Livetec has a culling standby contract with the broiler industry that allows it to maintain equipment and technology to be used in the event of a notifiable disease outbreak. It was also involved in dealing with the AI outbreak in Hampshire in February this year. It managed the culling and clean up operation for Mackenzie Brothers, whose broiler breeder unit at Upham, near Winchester suffered an outbreak of a low path strain of the virus. Some 10,000 birds were culled.

The scale of the operation at Staveleys is much bigger. A total of 170,000 birds -120,000 cage and 50,000 free range – have been culled and the virus involved is a high path version. The cost of the clean-up at Preston is expected to be far higher than the bill for the clean-up in Hampshire. Julian Sparrey could not reveal the cost involved in the Upham outbreak, but on the infection near Preston he said, “I wouldn’t like to think what the cost will be there.”

Whilst the Government takes responsibility for the preliminary cleansing and disinfection of an affected site, the bill for the secondary cleansing and disinfection is borne by the farmer. The work involves not only cleaning out the sheds, but also the secure removal of the waste water from cleaning the sheds and the cost of dealing with the chicken litter.

A recent outbreak of bird flu involving a high path strain of the virus occurred in Yorkshire in November. A total of 6,000 birds were culled on a duck breeding unit at Nafferton, Driffield. The Ranger understands from other sources that the cost of the clean-up operation at Nafferton amounted to about £10 per bird.

Julian Sparrey agreed with our estimate that £10 per bird could well be a reasonable average to put on clean-up costs, although he said that the bill would vary depending on the circumstances at each individual farm. “It is very difficult to give a price per head because each farm will de different,” said Julian.

Cleaning out the sheds after avian influenza is, in itself, far more costly than a normal clean down. Steve Birchall told the Ranger that the cost of a single clean would be nearly 50 per cent more than usual because of the nature of the cleaning required and because of the restrictions placed on the workforce. “We have to be far more meticulous and the workers who are involved are not allowed to go to any other site for four or five days afterwards. That time has to be paid,” said Steve. For the secondary cleansing and disinfection the cleaning process has to be carried out twice, according to rules laid down by the Department for Environment, Food and Rural Affairs (Defra). Additional cleans may be required if APHA is not satisfied with the result.

The cleaning process can also be far more difficult in cage units – particularly in older buildings. The Ranger understands that some of the heaviest costs facing the Staveleys are for the cage units on the farm. There have been reports that the Staveleys may even be considering pulling some sheds down.

In addition to the bill for cleaning the sheds, there are other significant costs for any producer looking to recover from an outbreak. One of them is the cost of removing waste water. The waste water can only go to a site with the necessary environmental approvals. Julian Sparrey said that providing the necessary facilities to handle the water on site could cost £30,000 and finding a suitable treatment works to take the water nearby could also be a problem. “It is not always easy,” he said. “We were involved in one case where the nearest approved treatment works prepared to take the water was 400 miles away. There were a lot of tanker trips involved,” he said.

Once avian influenza has been confirmed on a farm, all movements to and from the site, as well as the clean-up operation, itself, are tightly controlled by the Animal and Plant Health Agency (APHA). At Staveleys, the culling of the birds began on July 11 and was completed on July 14. Subsequent working restrictions are placed upon any catchers who have been involved in operations in the infected sheds. Like the cleaners, they are not allowed on another site for four or five days afterwards. There are reports of some worried producers telling catchers to stay away from their farms for up to three weeks after working on an infected site.Preliminary cleansing and disinfection at Staveleys was completed on the evening of July 16. It is the secondary cleansing and disinfection that are the responsibility of the farmer.

However, although the farmer is responsible, everything has to be agreed by animal health teams. Julian Sparrey says that the procedures are very stringent. “An approved process for the cleaning has to be agreed with animal health,” he said. “The procedure that is to be used is agreed and written down. Once that is done it becomes a legal document and if you divert from that at all you could be fined £6,000 and face a month in jail. That is how strict it is.”

He said that any piece of equipment entering or leaving the infected site would have to be licensed. Julian said that if he was to be managing an on-farm operation he would probably have portable buildings on the site for workers involved in the clean-up. Facilities would include showers so that the workers could clean themselves down at the end of the day and avoid carrying any infection off the affected farm.

He said that, during a bird flu outbreak, animal health would be on site constantly, checking and overseeing everything that was being done. Everything that needed to be done would require approval and cleaning would be closely monitored. “They will go around wearing white gloves. They will wipe their hands across a surface and if there is the slightest dirt you will be told to do it again,” said Julian. “It is a nightmare for anyone who is unfortunate enough to be affected. Animal Health people are all over you all day.”

The removal of litter was also closely monitored, he said. The muck could be stored on the farm, itself, although it would have to be stacked and covered in a bio-secure way – probably on hard standing so that no infection could leach out into the environment. It would have to be stored for a minimum of 42 days and, if it was stored on site, the farm could not be declared clean whilst it was there. After the 42 days the litter could be disposed of normally, he said.

Another option – one which had been used by some affected farmers – was to find somewhere away from the farm where the muck could be stored for the 42 days. The Ranger understands that the owner of the Yorkshire duck farm hit by AI in November last year made arrangements for the muck to be stored on an airfield.

Another alternative, said Julian, was to send the muck for rendering. This could be done straight away if a suitable plant could be found that was willing to take the litter, although the muck would have to be moved by approved transport to avoid cross-contamination. If this was done, said Julian, only relatively small amounts of litter could be moved at one time. The litter did not render easily on its own and so had to be mixed with other materials. There was also the issue of washing down trucks at the rendering plant to ensure that the virus was not passed on. Compared with stacking the litter, rendering is a more expensive option, although it allows the waste to be moved off farm quickly.

Egg producers will, of course, hope that they never have to deal with the devastating effects of bird flu. Julian Sparrey says that, whilst most people will never be affected, everyone should have plans in place in case the worst should happen. “Know beforehand exactly what you will do if it happens. Is there somewhere you would be able to store the litter away from the farm if you needed to, for example? It is best to be prepared.”

Some producers have made preparations by investing in AI insurance. The Ranger understands that the Staveleys were insured against possible outbreak. However, it would appear that existing insurance policies may well have underestimated the high costs of secondary cleansing and disinfection. Recent outbreaks have shown that the clean-up costs account for a very large part of the bill for an AI outbreak.

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Dossier H5N2: Virus likely spreads by multiple routes

Robert Roos, CIDRAP, June 15, 2015: The US Department of Agriculture’s (USDA’s) initial studies of how the H5N2 highly pathogenic avian influenza (HPAI) virus invades poultry farms point to no one clear factor but suggest that the explanation probably includes biosecurity gaps and possibly airborne transmission, the agency announced today.

The USDA’s Animal and Plant Health Inspection Service (APHIS) “cannot . . . associate HPAI transmission with one factor or group of factors in a statistically significant way at this time, and will continue to update this report regularly as more analyses are completed,” the agency said in a statement.

The USDA’s first epidemiologic report on the H5N2 situation reiterates the agency’s view that wild birds introduced H5N2 and H5N8 avian flu into commercial poultry originally, but says it is apparently spreading in other ways as well, given the number and proximity of farms affected.

“For instance, the report provides evidence that a certain cluster of farms was affected by identical viruses, pointing to possible transmission among those farms,” the statement said. “In addition, genetic analyses of the HPAI viruses suggest that independent introductions as well as transmission between farms were occurring in several States concurrently.”

The report says informal observations point to biosecurity lapses as a likely contributor to transmission. It also describes air sampling and wind studies that suggest a possible role for airborne spread of the virus.

Four types of studies included
The 38-page report includes findings from questionnaires completed by operators of 81 turkey farms in five states, comparisons of wind direction and speeds with outbreak patterns, air sampling studies conducted at six farms, and an analysis of virus isolates.

The report does not include any systematic study of biosecurity practices, but it says that biosecurity lapses are “a likely cause of some virus transmission.”

“For example, APHIS has observed sharing of equipment between an infected and noninfected farm, employees moving between infected and noninfected farms, lack of cleaning and disinfection of vehicles moving between farms, and reports of rodents or small wild birds inside poultry houses,” it states. “We are compiling these observations and will present our findings in a subsequent update of this report.”

The document gives little clue how common or widespread such lapses are, but the questionnaire responses show that wild birds have been seen inside poultry barns on 25% of the farms.

The survey part of the study includes findings from infected turkey farms in Iowa (2), Minnesota (67), North Dakota (2), South Dakota (6), and Wisconsin (4). The survey’s aim was to gather descriptive information that could generate hypotheses about “disease predilection.”

The report says investigators were asked to complete a survey for at least one non-infected farm located near each infected one, but the numbers of both were too small to allow for a statistical comparison.

Air sampling results
In May a University of Minnesota researcher who works with the USDA said she and her colleagues found H5N2 virus material in air samples taken inside and outside infected poultry barns, suggesting that the virus may be able to spread through the air. The USDA report provides more details on those findings.

Investigators took air samples at three Minnesota turkey farms and three layer flocks in Iowa and Nebraska, the report explains. Samples were collected inside affected barns, immediately outside, and at sites ranging from 70 to 1,000 meters downwind from them.

Close to half (46%) of the indoor samples contained H5N2 virus material, as did 23% of the immediate outside samples, but only 2% of the more distant locations yielded positive samples. At least one air sample tested positive for 5 of the 6 flocks included.

In addition to air samples, the researchers also collected samples from surfaces directly exposed to air exhausted from two of the layer chicken barns. At one of the sites, 63% of the samples tested positive, and at the other, 45% had “suspect” results.

The findings of viral material don’t necessarily mean viable virus particles were present. But the researchers did isolate viable H5 virus from one air sample collected inside a turkey barn, and results from the layer farms are still pending, the report says.

“The limited detection of viable virus does not necessarily indicate that the virus was not viable since the sampling process could contribute to the inactivation of the virus,” the report states.

“The implications of these findings in terms of understanding the transmission of HPAI between flocks need further investigation and we hypothesize that both the transport of airborne particles and the deposition of infectious airborne particles on the surfaces around infected premises represents a risk for the spread of HPAI to other locations,” it says.

Wind-related findings
USDA investigators used two ways to look into the possible role of wind in spreading H5N2: by comparing wind direction and farm locations in a cluster of Minnesota outbreaks, and by assessing outbreaks that followed periods of high winds.

In a geospatial analysis, researchers charted general wind directions in four adjacent Minnesota counties between Mar 23 and Apr 2 and charted the direction in which outbreaks spread during that time.

Although the methods used were very limited, they showed very little alignment between wind direction and the direction of avian flu transmission, the report says. Winds, while highly variable, blew predominantly from the west-northwest, whereas outbreaks generally spread from northeast to southwest.

On the other hand, investigators did see some signs that high winds could help spread H5N2, according to the report. On the basis of veterinarians’ observation in Minnesota, “sustained high wind speeds over two days appeared to be related to clusters of outbreaks 5-7 days later.”

For example, the first periods of sustained high winds of the season came around Mar 22, and the first batch of avian flu investigations followed on Mar 29 and Apr 1, the agency said. A second spell of high winds occurred around Apr 5, and it was followed by a large number of outbreak investigations about Apr 12.

The report cautions that the findings represent only a visual comparison, not a statistical analysis, and are based on data from just three weather stations. A more rigorous analysis is ongoing.

APHIS said its ongoing efforts to share avian flu information with state and industry partners include an animal health meeting in July that will focus specifically on biosecurity.

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Dossier Transmission: Animal-to-Human transmission of H7H7 in Holland 2003

The outbreak of highly pathogenic avian influenza A virus subtype H7N7 started at the end of February, 2003, in commercial poultry farms in the Netherlands. In this study, published in The Lancet in 2004, it is noted that an unexpectedly high number of transmissions of avian influenza A virus subtype H7N7 to people directly involved in handling infected poultry, providing evidence for person-to-person transmission.

Although the risk of transmission of these viruses to humans was initially thought to be low, an outbreak investigation was launched to assess the extent of transmission of influenza A virus subtype H7N7 from chickens to humans.

Most H7 cases were detected in the cullers. The attack rate (proportion of persons at risk that developed symptoms) of conjunctivitis was highest in veterinarians, and both cullers and veterinarians had the highest estimated attack rate of confirmed A/H7N7
infections.

453 people had health complaints—349 reported conjunctivitis, 90 had influenza-like illness, and 67 had other complaints. We detected A/H7 in conjunctival samples from 78 (26·4%) people with conjunctivitis only, in five (9·4%) with influenza-like illness and conjunctivitis, in two (5·4%) with influenza-like illness only, and in four (6%) who reported other symptoms. Most positive samples had been collected within 5 days of symptom onset.

A/H7 infection was confirmed in three contacts (of 83 tested), one of whom developed influenza-like illness. In three of these exposed contacts an A/H7N7 infection was confirmed. All three were household contacts.The first contact was the 13-year-old daughter of a poultry worker, who developed conjunctivitis approximately 10 days after onset of symptoms in her father.Six people had influenza A/H3N2 infection. After 19 people had been diagnosed with the infection, all workers received mandatory influenza virus vaccination and prophylactic treatment with oseltamivir. More than half (56%) of A/H7 infections reported here arose before the vaccination and treatment programme.

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Dossier H5N1: Spatial, temporal and genetic dynamics of H5N1 in China

The spatial spread of H5N1 avian influenza, significant ongoing mutations, and long-term persistence of the virus in some geographic regions has had an enormous impact on the poultry industry and presents a serious threat to human health.

This study revealed two different transmission modes of H5N1 viruses in China, and indicated a significant role of poultry in virus dissemination. Furthermore, selective pressure posed by vaccination was found in virus evolution in the country.

Phylogenetic analysis, geospatial techniques, and time series models were applied to investigate the spatiotemporal pattern of H5N1 outbreaks in China and the effect of vaccination on virus evolution.

Results showed obvious spatial and temporal clusters of H5N1 outbreaks on different scales, which may have been associated with poultry and wild-bird transmission modes of H5N1 viruses. Lead–lag relationships were found among poultry and wild-bird outbreaks and human cases. Human cases were preceded by poultry outbreaks, and wild-bird outbreaks were led by human cases.

Each clade has gained its own unique spatiotemporal and genetic dominance. Genetic diversity of the H5N1 virus decreased significantly between 1996 and 2011; presumably under strong selective pressure of vaccination. Mean evolutionary rates of H5N1 virus increased after vaccination was adopted in China.

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Dossier H5N1: Different environmental drivers of outbreaks in poultry and wild birds

Different environmental drivers operate on HPAI H5N1 outbreaks in poultry and wild birds in Europe. The probability of HPAI H5N1 outbreaks in poultry increases in areas with a higher human population density and a shorter distance to lakes or wetlands.

This reflects areas where the location of farms or trade areas and habitats for wild birds overlap. In wild birds, HPAI H5N1 outbreaks mostly occurred in areas with increased NDVI and lower elevations, which are typically areas where food and shelter for wild birds are available.

The association with migratory flyways has also been found in the intra-continental spread of the low pathogenic avian influenza virus in North American wild birds. These different environmental drivers suggest that different spread mechanisms operate.

Disease might spread to poultry via both poultry and wild birds, through direct (via other birds) or indirect (e.g. via contaminated environment) infection. Outbreaks in wild birds are mainly caused by transmission via wild birds alone, through sharing foraging areas or shelters. These findings are in contrast with a previous study, which did not find environmental differences between disease outbreaks in poultry and wild birds in Europe.

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