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.


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.


Dossier AI transmission: After 5 month, transmission routes still unknown

By David Pitt, Associated Press: May 4,2015: Scientist work to answer questions about puzzling bird flu virus. It’s been five months since the H5N2 bird flu virus was discovered in the United States, and producers have lost 21 million birds in the Midwest alone. Yet researchers acknowledge they still know little about a bird flu virus that’s endangered turkey and egg-laying chicken populations that supply much of the nation.

Scientists at the U.S. Department of Agriculture, the Centers for Disease Control and Prevention and other federal agencies are puzzled by the H5N2 virus’s spread — even amid heightened biosecurity measures — and apparent lack of widespread deaths in largely unprotected backyard flocks. “At this point, we don’t know very much about these viruses because they’ve only recently been identified,” Dr. Alicia Fry, the CDC’s leader of the influenza prevention and control team, said. “We’re following the situation very closely because this is something we’re continuing to understand.”

The current H5N2 virus surfaced last winter in Canada and was first identified in the United States in early December, when it was found in a wild bird on the West Coast. This spring, the virus was found in poultry operations in eight Midwest states, forcing commercial producers to kill and compost millions of turkeys and chickens in Iowa, Minnesota and elsewhere.

Scientists speculate that perhaps rodents or small birds, seeking food, tracked the virus into barns. Maybe it’s the work of flies, as the bird flu virus has been found on the insects in a Pennsylvania outbreak in 1983 and in Japan in 2004. The USDA’s chief veterinarian even has floated the idea that wind may be blowing dust and feathers carrying the virus from the barnyard into buildings through air vents. “To me, the main concern is the disease is moving even with heightened biosecurity,” said Richard French, a professor of animal health at Becker College in Worcester, Massachusetts. “Ideally we’ve got to try and figure out the way it’s most likely moving and try to put controls in place to stop that.”

Poultry farms’ biosecurity measures include changing clothes and boots before entering barns, disinfecting equipment and vehicles before they approach barns, and assigning workers to specific barns. As new operations are infected almost daily, USDA epidemiologists also are trying to determine whether the virus came from a wild bird or could have spread from poultry in another barn or a nearby farm.
“We are continuing to evaluate how facilities become positive because we also want to be cognizant of any potential risk of lateral spread from farm to farm,” said Dr. T.J. Myers, the USDA associate deputy administrator of veterinary services. “We are doing those evaluations as we speak, and we really don’t have enough data to report on that yet.”

Another puzzling question has been why there hasn’t been a surge in infections of backyard flocks. The USDA has identified 12 cases including five in Washington in January and February, plus others in Idaho, Kansas, Minnesota, Montana, Oregon and Wisconsin.
Cases might not be reported, French said, noting that commercial operations have a financial incentive to immediately report illnesses because the government pays them for each live bird that must be destroyed. Plus, French said, outdoor chickens could have been exposed over time to low pathogenic versions of bird flu and have developed stronger immunity.

One belief held by researchers will soon be tested: whether the virus will die as temperatures warm and ultraviolet light increases. With temperatures this week in the 70s in many of the affected states and even warmer weather expected soon, infections should decline if that assumption is true.

But David Swayne, director of the Southeast Poultry Research Laboratory in Athens, Georgia, acknowledged it’s hard to predict what will happen. “It’s pretty complex. It involves the climate, the temperature itself, the amount of humidity there,” he said.
Scientists expect the virus to return in the fall along with cooler temperatures and wild birds migrating south, but Swayne says the virus could burn itself out and disappear for a while before that.

Amid all the questions is one about the human element: Could the virus spread to people? So far, it hasn’t, but significant efforts are underway to develop a vaccine just in case. “We’re cautiously optimistic that we will not see any human cases, but there certainly is a possibility that we may,” Fry said.


Dossier AI in the USA: Massive blow to the Minnesota turkey industry

The commercial turkey industry in Minnesota has been hit hard by the current HPAI outbreak. Could this been prevented? Is the USA prepared for large-scale outbreaks of Avian Influenza?

Does the United States have the strongest AI surveillance program in the world, as claimed on the website of USDA APHIS? If so, how come that the current outbreak was detected in Canada, weeks or even longer before the first outbreaks within the poultry population were detected just on the other side of the border in the US?

And why doesn’t the AI surveillance program include large-scale active field surveillance within the wild birds population? Why took it so long before the potential impacts associated with the introduction of HPAI viruses into wild bird populations were understood by the industry?

The current epidemiological efforts are insufficient to determine the risks of other farms getting infected, because the mechanism of infection the current flocks is still unknown. Active laboratory surveillance is not the answer either to predict future outbreaks: Massive efforts in active field-based epidemiological research under wild birds and in wetlands are needed to as part of an early warning system; hunting, fishing and other activities that take place in the wetland areas have to be banned to prevent humans to enter the HPAI infection to the farm; and all commercial turkey farms need to be completely isolated as long as the risks of outbreaks is eminent.

Compared to other poultry species, turkeys need only 1/100 of the normal virus load on contaminated materials (soil, organic materials etc.) to become infected, with lethal consequences for the birds, and enormous financial consequences for the farming industry.

The turkey industry is still completely in the dark about the current outbreak situation. The USDA APHIS active laboratory surveillance programs might be one of the best in the world, is clearly not enough under the current circumstances to determine whether a flock has become infected. Unless the efforts to collect more valid data is substantially increased, followed by rigorous epidemiological analysis and a solid risk assessment, the turkey industry in Minnesota will probably see more outbreaks to come in the near future.


Dossier investigation: identification of the agent

Influenza in birds is caused by infection with viruses of the family Orthomyxoviridae placed in the genus influenzavirus A. Influenza A viruses are the only orthomyxoviruses known to naturally affect birds. Many species of birds have been shown to be susceptible to infection with influenza A viruses; aquatic birds form a major reservoir of these viruses, and the overwhelming majority of isolates have been of low pathogenicity (low virulence) for chickens and turkeys. Influenza A viruses have antigenically related nucleocapsid and matrix proteins, but are classified into subtypes on the basis of their haemagglutinin (H) and neuraminidase (N) antigens (World Health Organization Expert Committee, 1980). At present, 16 H subtypes (H1–H16) and 9 N subtypes (N1–N9) are recognised with proposed new subtypes (H17, H18) for influenza A viruses from bats in Guatemala (Swayne et al., 2013; Tong et al., 2012; 2013). To date, naturally occurring highly pathogenic influenza A viruses that produce acute clinical disease in chickens, turkeys and other birds of economic importance have been associated only with the H5 and H7 subtypes. Most viruses of the H5 and H7 subtype isolated from birds have been of low pathogenicity for poultry. As there is the risk of a H5 or H7 virus of low pathogenicity (H5/H7 low pathogenicity avian influenza [LPAI]) becoming highly pathogenic by mutation, all H5/H7 LPAI viruses from poultry are notifiable to OIE. In addition, all high pathogenicity viruses from poultry and other birds, including wild birds, are notifiable to the OIE.


Basic information about avian influenza

Avian influenza is usually an inapparent or nonclinical viral infection of wild birds that is caused by a group of viruses known as type A influenzas. These viruses are maintained in wild birds by fecal-oral routes of transmission. This virus changes rapidly in nature by mixing of its genetic components to form slightly different virus subtypes. Avian influenza is caused by this collection of slightly different viruses rather than by a single virus type. The virus subtypes are identified and classified on the basis of two broad types of antigens, hemagglutinan (H) and neuraminidase (N); 15 H and 9 N antigens have been identified among all of the known type A influenzas.


Dossier HPAI: The complete STOP AI Training Manual

In 2007, USAID launched a worldwide program to battle outbreaks of Avian Influenza under the name STOP AI: Stamping Out Pandemic & Avian Influenza.

This program was one of the largest Training of trainer programs on Avian Influenza of its kind, with training programs conducted in more than 40 countries.

The training manual contains valuable training materials, presentations, background information and references on various subjects:

Module 1 – Overview of Avian Influenza
Module 2 – National Preparedness & Response Plans for HPAI
Module 3 – OIE Avian Influenza Standards and FAO Emergency Prevention System
Module 4 – Public Health and Occupational Safety
Module 5 – Animal Surveillance
Module 6 – Sample Collection and Transport
Module 7 – GIS and Outbreak Mapping
Module 8 – Biosecurity
Module 9 – Introduction to Outbreak Response
Module 10 – Depopulation, Disposal, and Decontamination
Module 11 – Recovery Options.

This training course was intended for animal and human health experts who have limited experience with avian influenza, but who do have field experience with other animal, zoonotic, or infectious diseases. This course includes modules on avian influenza virology, epidemiology, response, and recovery.


Dossier Vaccination: The basics explained on the use of vaccination in poultry production

Dr. Ossama Motawae, an Egyptian veterinarian, posted an interesting presentation online, explaining the basics of vaccination. Poultry vaccines are widely applied to prevent and control contagious poultry diseases. Their use in poultry production is aimed at avoiding or minimizing the emergence of clinical disease at farm level, thus increasing production.

Vaccines and vaccination programs vary broadly in regard to several local factors (e.g. type of production, local pattern of disease, costs and potential losses) and are generally managed by the poultry industry.

In the last decade, the financial losses caused by the major epidemic diseases of poultry (avian influenza and Newcastle disease) have been enormous for both the commercial and the public sectors.

Thus, vaccination should also be applied in the framework of poultry disease eradication programs at national or regional levels under the official supervision of public Veterinary Services. This paper provides insight on the use of vaccination for the control of poultry infections, with particular emphasis on the control of trans-boundary poultry diseases.


Animal Health Crisis Management and Disease Control in Asia

At the invitation of DG SANCO, EFSA participated in the context of the Shanghai Expo 2010 in China to the Sino-European Food Safety Cooperation Forum, to the Seminar on Research for Healthy life and to the Securing Food Safety for a Healthy Life Day from 4 to 11 June.

Former Chief Veterinary Officer of FAO, Mr. Joseph Domenech delivered a lecture on Animal Health Crisis Management in with respect to Avian Influenza Control in Asia. The event was organised as part of the Better Training for Safer Food programme, which aims to train staff in Member States and Third Countries in official controls on food. The forum provided presentations and lectures by staff of the European Commission, the European Food Safety Authority and Member States.

Lectures were also given by representatives of the Chinese General Administration for Quality Supervision, Inspection and Quarantine (AQSIQ), the Ministry of Health, and the Ministry of Agriculture.


Creating Nitrogen on location: important new animal welfare application

This is the second presentation of a series of documents, presented during the conference on the application of the Anoxia method for euthanizing animals.

The conference is held in Canberra (Australia) on February 21, 2014. The conference is organized for representatives of animal welfare organizations, Australian animal health authorities and the industry gives a general overview of the Anoxia technique.