You’re welcome to participate at the International seminar on September 23, 2015

Animal welfare during contagious disease outbreaks: Preventive isolation measures instead of large-scale culling programs?

Although the spring outbreaks of Highly Pathogen Avian Influenza in Europe and North America are finally behind us, the discussions on what caused these outbreaks and why specific parts of the industry were hit so severely are just beginning. In these discussions, the financial impact for the industry has the highest priority and animal welfare seems to be of secondary importance.

It is likely that outbreaks may reappear in the fall months when temperatures begin to drop and wild birds begin to migrate for the winter, causing similar disease issues in coming autumn, jeopardizing the animal welfare rights of poultry again.

To minimize the impact on the poultry industry as well as to minimize the risk that animals need to be culled, it’s important to understand how the initial transmission of HPAI takes place and to analyze the several ways the virus could be transmitted amongst farms. 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.

A revolutionary new – Neutralizing Risks – strategy would be based on applying new response techniques, based on: culling the animals without human – to – animal contact; integrating detergent application into the culling operations; combining culling & disposal into one activity.

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.

AVT participates in the seminar, discussing how to implement animal welfare in Standard Operating Procedures during culling of animals. Taking away the source of infection by culling the animals still remains a high priority, as long as it does not violate the other priorities of the strategy.

The recently introduced Anoxia technique, based on submerging poultry in high expansion foam filled with 98% nitrogen, safeguards not only animal welfare during response activities; the technique is also suitable to cull small numbers of birds, as well as large locks of poultry, regardless the housing system.

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, 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

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


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.


Dossier AI: Transmission of Avian Influenza Virus to Dogs

Avian influenza was found in a dog on a farm in South Gyeongsang Province amid growing concerns that the disease could spread to other animals, officials the Ministry of Agriculture, Food and Rural Affairs said. The dog ― one of three at a duck farm in Goseong-gun, South Gyeongsang Province ― had antigens for the highly pathogenic H5N8 strain of bird flu, the Ministry of Agriculture, Food and Rural Affairs said. The disease affected the farm on Jan. 23.

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. The antibody means the immune system of the dogs eliminated the virus. This is the first time bird flu has been found in a dog in Korea through the detection of antigens.

“None of these dogs had shown symptoms. No antigens or antibodies for the virus were found in the two other dogs, which means that dog-to-dog transmission is unlikely to have happened,” quarantine officials said.

The ministry suspected that the dog may have eaten infected animals at the farm. All poultry and dogs at the concerned farm were slaughtered as part of the preventive measures right after the farm was reported to have been infected with the disease, officials said.

Meanwhile, quarantine officials rejected the possibility of viral transmission to humans. According to the ministry’s report, about 450 workers at infected farms across the country had been given an antigen test, with none showing signs of infection. None of Korea’s 20,000 farm workers have reported any symptoms so far, officials added.

“It is thought that infected dogs do not show symptoms of the disease as they are naturally resistant to bird flu,” the ministry said. Meanwhile, the Agriculture Ministry has toughened the quarantine measures in Goseong-gun. The region is a frequented by migratory birds, which are suspected to have spread the viral disease.


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

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.


Dossier H5N1: Spreading patterns global H5N1 outbreaks match bird migration patterns

The global spread of highly pathogenic avian influenza H5N1 in poultry, wild birds and humans, poses a significant pandemic threat and a serious public health risk.

An efficient surveillance and disease control system relies on the understanding of the dispersion patterns and spreading mechanisms of the virus. A space-time cluster analysis of H5N1 outbreaks was used to identify spatio-temporal patterns at a global scale and over an extended period of time.

Potential mechanisms explaining the spread of the H5N1 virus, and the role of wild birds, were analyzed. Between December 2003 and December 2006, three global epidemic phases of H5N1 influenza were identified.

These H5N1 outbreaks showed a clear seasonal pattern, with a high density of outbreaks in winter and early spring (i.e., October to March). In phase I and II only the East Asia Australian flyway was affected. During phase III, the H5N1 viruses started to appear in four other flyways: the Central Asian flyway, the Black Sea Mediterranean flyway, the East Atlantic flyway and the East Africa West Asian flyway.

Six disease cluster patterns along these flyways were found to be associated with the seasonal migration of wild birds. The spread of the H5N1 virus, as demonstrated by the space-time clusters, was associated with the patterns of migration of wild birds. Wild birds may therefore play an important role in the spread of H5N1 over long distances.

Disease clusters were also detected at sites where wild birds are known to overwinter and at times when migratory birds were present. This leads to the suggestion that wild birds may also be involved in spreading the H5N1 virus over short distances.


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.


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 Anoxia Method: The sensible culling method for the use on organic farms

Organic poultry farming is the most responsively production system to produce healthy, good quality poultry meat and eggs in an ecologically way. It’s designed to avoid the need for agrochemicals and to minimize damage to the environment and wildlife.

Still, also organic poultry production is not free from the danger becoming infected by contagious diseases, like the current H5N2 outbreak in Canada and the USA.

All currently commercially available depopulation techniques focus on stamping out the virus, in an attempt to stop the spreading, not on maintaining animal welfare standards: methods like macerating birds alive; using CO2 in containers or throughout the entire poultry house; by electrocution; or by occlusion of the trachea with firefighting foam. This makes these techniques irreconcilable with the principle of organic farming, because the culling process with he current methods leave little room for the animal’s welfare rights in the last day of its existence.

Since June 2015, a new sensible culling technique is commercially available that serves both the goal to bring an outbreak to a stop and to maintain a high level of animal welfare during the process of culling for disease control purposes.

The Anoxia method is the most humane method to euthanize animals that are in severe pain or suffer severely seems to be the use of nitrogen gas foam. By this method the animals will be unconscious within a short time through an abundance of nitrogen. The animals die in a short time, without regaining consciousness.

The method of nitrogen gas foam uses a barrel, filled up with a layer of high expansion foam (big bubbles) completely filled with pure nitrogen. The animal will be placed in the foam and covered with a layer of foam of at least 60 centimetres. The animal will breathe 98 per cent nitrogen. The amount of oxygen in the blood diminishes very quickly and the animal will very soon be unconscious. Because of the extreme oxygen deficiency (anoxia) the animal dies within one and a half to two minutes. The animal will not regain consciousness and won’t notice that it dies.

The animal will be unaware that it breathes in pure nitrogen and it will not be harmful or painful for the animal because the normal air an animal breathes consists already of 78 per cent nitrogen. Inhalation of nitrogen is therefore not stressful, whereas for example with high concentrations of carbon dioxide the animal will try not to breathe.

The Anoxia method is not physically demanding on the farmer and his employees. The animals almost instantly lose consciousness after being dipped through the foam. Fixation of the animal to avoid them to hurt themselves during stunning is not needed, as necessary in most other methods. Because of the thick nitrogen foam layer and the amount of 98 per cent nitrogen it is certain that the animal will die. The chance that the method fails and the animal regain consciousness and won’t die, are next to zero.


Dossier H5N8: Dutch outbreak (2014) linked to sequences of strains from Asia

Genetic analysis of influenza A(H5N8) virus from the Netherlands indicates that the virus probably was spread by migratory wild birds from Asia, possibly through overlapping flyways and common breeding sites in Siberia. In addition to the outbreak in the Netherlands, several other outbreaks of HPAI (H5N8) virus infections were reported in Europe at the end of 2014 after exponentially increasing deaths occurred in chicken and turkey flocks.

Genetic sequences submitted to the EpiFlu database indicated that the viruses from Europe showed a strong similarity to viruses isolated earlier in 2014 in South Korea, China, and Japan. An H5N8 virus isolated from a wigeon in Russia in September 2014 is located in the phylogenetic tree near the node of all sequences for H5N8 viruses from Europe.

In regard to time, this location fits the hypothesized route of H5N8 virus introduction into Europe. Furthermore, for several reasons, it is highly likely that the introduction of HPAI (H5N8) virus into the indoor-layer farm in the Netherlands occurred via indirect contact.

First, despite intensive monitoring, H5N8 viruses have never been detected in commercial poultry or wild birds in the Netherlands.

Second, when the virus was detected, the Netherlands had no direct trade contact with other European countries or Asia that might explain a route of introduction.

Third, because of the severity of disease in galliforms, outbreaks of H5N8 in the Netherlands before November 2014 would have been noticed.


Dossier AI transmission: Wind-Mediated Spread of Avian Influenza Viruses

Avian influenza virus-infected poultry can release a large amount of virus-contaminated droppings that serve as sources of infection for susceptible birds. Much research so far has focused on virus spread within flocks. However, as fecal material or manure is a major constituent of airborne poultry dust, virus-contaminated particulate matter from infected flocks may be dispersed into the environment.

This study, demonstrates the presence of airborne influenza virus RNA downwind from buildings holding LPAI-infected birds, and the observed correlation between field data on airborne poultry and livestock associated microbial exposure and the OPS-ST model. These findings suggest that geographical estimates of areas at high risk for human and animal exposure to airborne influenza virus can be modeled during an outbreak, although additional field measurements are needed to validate this proposition. In addition, the outdoor detection of influenza virus contaminated airborne dust during outbreaks in poultry suggests that practical measures can assist in the control of future influenza outbreaks.

In general, exposure to airborne influenza virus on commercial poultry farms could be reduced both by minimizing the initial generation of airborne particles and implementing methods for abatement of particles once generated. As an example, emergency mass culling of poultry using a foam blanket over the birds instead of labor-intensive whole-house gassing followed by ventilation reduces both exposure of cullers and dispersion of contaminated dust into the environment, contributing to the control of influenza outbreaks.