Avian Influenza has become endemic in many parts of the word. In it's current form it has been around since 1997 and although thy virus types have changed, emergency response, management & control are still a hot issue. In this article published in 2006 in the US magazine Poultry Perspectives, the subject what to do during crisis situations is presented. The conclusions are still valid today and may help to prevent large-scale outbreaks
In this paper various bird welfare aspects related to avian influenza and other contagious diseases are discussed.
Disease outbreaks will, apart from the obvious direct effects on bird health, and thereby their wellbeing, also indirectly influence the welfare of the birds. For example, restrictions on outdoor access for free-range poultry may be imposed, and vaccination or testing schemes may lead to handling or sampling procedures that are stressful to the birds.
At the same time, the immediate risk of a disease outbreak may lead to improved biosecurity measures on farms, which may in turn decrease the risk of other diseases entering the premises, thus resulting in improved bird health and welfare.
Dossier transmission: Transmission of Avian Influenza Virus to DogsHarm Kiezebrink
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.
Per contact probability of infection by Highly Pathogenic Avian InfluenzaHarm Kiezebrink
Estimates of the per-contact probability of transmission between farms of Highly Pathogenic Avian Influenza virus of H7N7 subtype during the 2003 epidemic in the Netherlands are important for the design of better control and biosecurity strategies.
We used standardized data collected during the epidemic and a model to extract data for untraced contacts based on the daily number of infectious farms within a given distance of a susceptible farm.
With these data, the ‘maximum likelihood estimation’ approach was used to estimate the transmission probabilities by the individual contact types, both traced and untraced.
The outcomes were validated against literature data on virus genetic sequences for outbreak farms. The findings highlight the need to
1) Understand the routes underlying the infections without traced contacts and
2) To review whether the contact-tracing protocol is exhaustive in relation to all the farm’s day-to-day activities and practices.
AI transmission risks: Analysis of biosecurity measures and contact structureHarm Kiezebrink
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. Once a farm is infected, culling entire flock is the only option to prevent further spreading with devastating consequences for the industry.
In this paper, based on the HPAI outbreak in Holland 2003, the researchers found that 32 farms hired external labor of which seven accessed other poultry on the same day.
However, they were not the only ‘connectors’ as some (twelve) farmers also reported themselves helping on other poultry farms.
Furthermore, 27 farms had family members visiting poultry or poultry-related businesses of which nine entered poultry houses during those visits. The other enhancing factor of farm interconnections was the reported ownership of multiple locations for ten of the interviewed farms and the reported on-premises sale of farm products on one pullet and eight layer farms.
Also worth mentioning is the practice of a multiple age system reported on eight of the interviewed farms as this may increase the risk of infecting remaining birds when off-premises poultry movements occur.
AI viruses may be introduced into poultry from reservoirs such as aquatic wild birds but the mechanisms of their subsequent spread are partially unclear. Transmission of the virus through movements of humans (visitors, servicemen and farm personnel), vectors (wild birds, rodents, insects), air- (and dust-) related routes and other fomites (e.g., delivery trucks, visitors’ clothes and farm equipment) have all been hypothesized.
It is therefore hypothesized that the risk of introducing the virus to a farm is determined by the farm’s neighborhood characteristics, contact structure and its biosecurity practices.
On the one hand, 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.
On the other hand, contact structure risk factors include the nature and frequency of farm visits. Therefore, a detailed analysis of the contact structure, including neighborhood risks, and biosecurity practices across different types of poultry farms and poultry-related businesses helps the improvement of intervention strategies, biosecurity protocols and adherence to these, as well as contact tracing protocols.
Farmers’ perception of visitor- and neighborhood-associated risks of virus spread is also important due to its relevance to adherence with biosecurity protocols, to contact tracing and to communicating advice to them.
Human-to-Human transmission of H7H7 in Holland 2003Harm Kiezebrink
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.
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. 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.
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.
Different environmental drivers of H5N1 outbreaks in poultry and wild birdsHarm Kiezebrink
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.
Spatial, temporal and genetic dynamics of H5N1 in chinaHarm Kiezebrink
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.
In this paper various bird welfare aspects related to avian influenza and other contagious diseases are discussed.
Disease outbreaks will, apart from the obvious direct effects on bird health, and thereby their wellbeing, also indirectly influence the welfare of the birds. For example, restrictions on outdoor access for free-range poultry may be imposed, and vaccination or testing schemes may lead to handling or sampling procedures that are stressful to the birds.
At the same time, the immediate risk of a disease outbreak may lead to improved biosecurity measures on farms, which may in turn decrease the risk of other diseases entering the premises, thus resulting in improved bird health and welfare.
Dossier transmission: Transmission of Avian Influenza Virus to DogsHarm Kiezebrink
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.
Per contact probability of infection by Highly Pathogenic Avian InfluenzaHarm Kiezebrink
Estimates of the per-contact probability of transmission between farms of Highly Pathogenic Avian Influenza virus of H7N7 subtype during the 2003 epidemic in the Netherlands are important for the design of better control and biosecurity strategies.
We used standardized data collected during the epidemic and a model to extract data for untraced contacts based on the daily number of infectious farms within a given distance of a susceptible farm.
With these data, the ‘maximum likelihood estimation’ approach was used to estimate the transmission probabilities by the individual contact types, both traced and untraced.
The outcomes were validated against literature data on virus genetic sequences for outbreak farms. The findings highlight the need to
1) Understand the routes underlying the infections without traced contacts and
2) To review whether the contact-tracing protocol is exhaustive in relation to all the farm’s day-to-day activities and practices.
AI transmission risks: Analysis of biosecurity measures and contact structureHarm Kiezebrink
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. Once a farm is infected, culling entire flock is the only option to prevent further spreading with devastating consequences for the industry.
In this paper, based on the HPAI outbreak in Holland 2003, the researchers found that 32 farms hired external labor of which seven accessed other poultry on the same day.
However, they were not the only ‘connectors’ as some (twelve) farmers also reported themselves helping on other poultry farms.
Furthermore, 27 farms had family members visiting poultry or poultry-related businesses of which nine entered poultry houses during those visits. The other enhancing factor of farm interconnections was the reported ownership of multiple locations for ten of the interviewed farms and the reported on-premises sale of farm products on one pullet and eight layer farms.
Also worth mentioning is the practice of a multiple age system reported on eight of the interviewed farms as this may increase the risk of infecting remaining birds when off-premises poultry movements occur.
AI viruses may be introduced into poultry from reservoirs such as aquatic wild birds but the mechanisms of their subsequent spread are partially unclear. Transmission of the virus through movements of humans (visitors, servicemen and farm personnel), vectors (wild birds, rodents, insects), air- (and dust-) related routes and other fomites (e.g., delivery trucks, visitors’ clothes and farm equipment) have all been hypothesized.
It is therefore hypothesized that the risk of introducing the virus to a farm is determined by the farm’s neighborhood characteristics, contact structure and its biosecurity practices.
On the one hand, 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.
On the other hand, contact structure risk factors include the nature and frequency of farm visits. Therefore, a detailed analysis of the contact structure, including neighborhood risks, and biosecurity practices across different types of poultry farms and poultry-related businesses helps the improvement of intervention strategies, biosecurity protocols and adherence to these, as well as contact tracing protocols.
Farmers’ perception of visitor- and neighborhood-associated risks of virus spread is also important due to its relevance to adherence with biosecurity protocols, to contact tracing and to communicating advice to them.
Human-to-Human transmission of H7H7 in Holland 2003Harm Kiezebrink
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.
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. 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.
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.
Different environmental drivers of H5N1 outbreaks in poultry and wild birdsHarm Kiezebrink
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.
Spatial, temporal and genetic dynamics of H5N1 in chinaHarm Kiezebrink
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.
H5N8 virus dutch outbreak (2014) linked to sequences of strains from asiaHarm Kiezebrink
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.
Outbreak of High Patogen Avian Influenza H5N8 in GermanyHarm Kiezebrink
Germany has reported an outbreak of highly pathogenic avian influenza, H5N8 in fattening turkeys in North East Germany
(Mecklenburg - Western Pomerania). Increased mortality was observed in one of the six sheds of 15 week old birds for fattening (total number of turkeys on the premises ~ 31,000 of which each shed contained 5,000).
Deadly H5N1 birdflu needs just five mutations to spread easily in peopleHarm Kiezebrink
Reference: Phys.org. 15 Apr 2014. Dutch researchers have found that the virus needs only five favorable gene mutations to become transmissible through coughing or sneezing, like regular flu viruses.
World health officials have long feared that the H5N1 virus will someday evolve a knack for airborne transmission, setting off a devastating pandemic. While the new study suggests the mutations needed are relatively few, it remains unclear whether they're likely to happen outside the laboratory.
Modelling wind-borne spread of HPAI between farms (2012)Harm Kiezebrink
To understand the risks of spreading contaminated materials caused by stable gassing, a quantitative understanding of the spread of contaminated farm dust between locations is a prerequisite for obtaining much-needed insight into one of the possible mechanisms of disease spread between farms.
The researchers Amos Ssematimba, Thomas J. Hagenaars, Mart C. M. de Jong of the Dutch Department of Epidemiology, Crisis Organization and Diagnostics, Central Veterinary Institute (CVI) part of Wageningen University and Research Centre, Lelystad, The Netherlands, and Quantitative Veterinary Epidemiology, Department of Animal Sciences, Wageningen University, Wageningen, The Netherland developed a model to calculate the quantity of contaminated farm-dust particles deposited at various locations downwind of a source farm and apply the model to assess the possible contribution of the wind-borne route to the transmission of Highly Pathogenic Avian Influenza virus (HPAI) during the 2003 epidemic in the Netherlands.
The model is obtained from a Gaussian Plume Model by incorporating the dust deposition process, pathogen decay, and a model for the infection process on exposed farms.
Using poultry- and avian influenza-specific parameter values we calculate the distance-dependent probability of between-farm transmission by this route.
A comparison between the transmission risk pattern predicted by the model and the pattern observed during the 2003 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.
Spatio temporal dynamics of global H5N1 outbreaks match bird migration patternsHarm Kiezebrink
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.
Overview of recent outbreaks of H5N8-High Pathogen Avian Influenza in Europe...Harm Kiezebrink
Updated outbreak assessment on Highly Pathogenic Avian Influenza: Europe, America and the Middle East. By the DEFRA, Veterinary & Science Policy Advice Team - International Disease Monitoring.
Influenza in birds is caused by infection with viruses of the family Orthomyxoviridae placed in the genus influenza virus 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.
FLI Seminar on different response strategies: Stamping out or NeutralizationHarm Kiezebrink
During this spring, American poultry producers are losing 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
The misunderstood epidemiological determinants of covid 19, problems and solu...Bhoj Raj Singh
COVID-19, a viral disease, fought with political means for socio-economic gains, will keep on haunting humanity for long. Without doing any epidemiological study on COVID-19 we have determined its modulators and determinants not to win over COVID-19 but to create misunderstanding to persist for long in inquisitive minds to blur the vision for novel inventions. This presentation deals with COVID-19 in general and misunderstood disease determinants in particular to suggest possible means to win over the disease. As the tip of COVID-19 iceberg is illusion and reality unknown, thus the struggle is endless.
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.
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.
Supplementary information wind mediated transmission HPAIHarm Kiezebrink
A comparison between the transmission risk pattern predicted by the model and the pattern observed during the 2003 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.
In this generic overview, you will find the date used in the publication “Modelling the Wind-Borne Spread of Highly Pathogenic Avian Influenza Virus between Farms”, published February 2012 (http://n2gf.com/?p=2377). For the outbreak of avian influenza A(H7N7) in the Netherlands in 2003, much data are available. The overview gives a description of the data used in the analyses of the mentioned publication:
Epidemiological data
There were 5360 poultry farms in the Netherlands in 2003, for all of which geographical information x is available. For 1531 farms the flocks were culled, for all of these the date of culling Tcull is known. For 227 of the 241 infected farms the date of infection tinf has been estimated, based on mortality data. The remaining 14 farms are hobby farms, defined as farms with less than 300 animals, for which no mortality data are available.
The geographic and temporal data together have previously been used to estimate the critical farm density, i.e. above what density of farms outbreaks are can occur.
Genetic data
The HA, NA and PB2 genes of viral samples from 231 farms have previously been sequenced. Sequence data RNA can be found in the GISAID database under accession numbers EPI ISL 68268-68352, EPI ISL 82373-82472 and EPI ISL 83984-84031. These data have previously been used to give general characteristics of the outbreak, to reconstruct the transmission tree and to assess the public health threat due to mutations of the virus in the animal host.
Meteorological data
Available meteorological data include wind speed wv and direction wdir (with a ten degree precision) and the fraction of time r without precipitation for every hour of every day of the outbreak, measured at five weather stations close to the infected farms. These data are available from the Royal Dutch Meteorological Institute at www.knmi.nl.
What would a flu pandemic in the USA look like? More like a war than a natura...Harm Kiezebrink
What would a flu pandemic in the U.S. look like? More like a war than a natural disaster, a government report indicates.
The USA is by far one of the best-prepared countries in the world when it comes to managing possible outbreak situations. This recently declassified Department of Defense report, dated August 2009, estimates that a full-blown flu pandemic could sicken about 30% of the U.S. population, leading to 3 million hospitalizations and 2 million deaths.
This Implementation Plan for Pandemic Influenza of the US Department of Defense directs how to prepare for, detect, respond to and contain the effect of a pandemic on military forces, DOD civilians, DOD contractors, dependents and beneficiaries.
Additionally, it addresses the provision of the US Department Of Defense assistance to civil authorities, foreign and domestic, as well as key security concerns such as humanitarian relief and stabilization operations that may arise.
A very interesting report that you NEED to read!
Lotta Berg 2009 on farm killing poultry at the Nordic Poultry conference in R...Harm Kiezebrink
This document was presented at the Nordic Poultry conference in Reykjavik in November 2009, before the Anoxia method was commercially available.
Dr. Berg compares in this document different methods of emergency killing of poultry, applicable within the Nordic poultry industry (Sweden, Norway, Denmark, Finland and Iceland).
H5N8 virus dutch outbreak (2014) linked to sequences of strains from asiaHarm Kiezebrink
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.
Outbreak of High Patogen Avian Influenza H5N8 in GermanyHarm Kiezebrink
Germany has reported an outbreak of highly pathogenic avian influenza, H5N8 in fattening turkeys in North East Germany
(Mecklenburg - Western Pomerania). Increased mortality was observed in one of the six sheds of 15 week old birds for fattening (total number of turkeys on the premises ~ 31,000 of which each shed contained 5,000).
Deadly H5N1 birdflu needs just five mutations to spread easily in peopleHarm Kiezebrink
Reference: Phys.org. 15 Apr 2014. Dutch researchers have found that the virus needs only five favorable gene mutations to become transmissible through coughing or sneezing, like regular flu viruses.
World health officials have long feared that the H5N1 virus will someday evolve a knack for airborne transmission, setting off a devastating pandemic. While the new study suggests the mutations needed are relatively few, it remains unclear whether they're likely to happen outside the laboratory.
Modelling wind-borne spread of HPAI between farms (2012)Harm Kiezebrink
To understand the risks of spreading contaminated materials caused by stable gassing, a quantitative understanding of the spread of contaminated farm dust between locations is a prerequisite for obtaining much-needed insight into one of the possible mechanisms of disease spread between farms.
The researchers Amos Ssematimba, Thomas J. Hagenaars, Mart C. M. de Jong of the Dutch Department of Epidemiology, Crisis Organization and Diagnostics, Central Veterinary Institute (CVI) part of Wageningen University and Research Centre, Lelystad, The Netherlands, and Quantitative Veterinary Epidemiology, Department of Animal Sciences, Wageningen University, Wageningen, The Netherland developed a model to calculate the quantity of contaminated farm-dust particles deposited at various locations downwind of a source farm and apply the model to assess the possible contribution of the wind-borne route to the transmission of Highly Pathogenic Avian Influenza virus (HPAI) during the 2003 epidemic in the Netherlands.
The model is obtained from a Gaussian Plume Model by incorporating the dust deposition process, pathogen decay, and a model for the infection process on exposed farms.
Using poultry- and avian influenza-specific parameter values we calculate the distance-dependent probability of between-farm transmission by this route.
A comparison between the transmission risk pattern predicted by the model and the pattern observed during the 2003 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.
Spatio temporal dynamics of global H5N1 outbreaks match bird migration patternsHarm Kiezebrink
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.
Overview of recent outbreaks of H5N8-High Pathogen Avian Influenza in Europe...Harm Kiezebrink
Updated outbreak assessment on Highly Pathogenic Avian Influenza: Europe, America and the Middle East. By the DEFRA, Veterinary & Science Policy Advice Team - International Disease Monitoring.
Influenza in birds is caused by infection with viruses of the family Orthomyxoviridae placed in the genus influenza virus 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.
FLI Seminar on different response strategies: Stamping out or NeutralizationHarm Kiezebrink
During this spring, American poultry producers are losing 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
The misunderstood epidemiological determinants of covid 19, problems and solu...Bhoj Raj Singh
COVID-19, a viral disease, fought with political means for socio-economic gains, will keep on haunting humanity for long. Without doing any epidemiological study on COVID-19 we have determined its modulators and determinants not to win over COVID-19 but to create misunderstanding to persist for long in inquisitive minds to blur the vision for novel inventions. This presentation deals with COVID-19 in general and misunderstood disease determinants in particular to suggest possible means to win over the disease. As the tip of COVID-19 iceberg is illusion and reality unknown, thus the struggle is endless.
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.
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.
Supplementary information wind mediated transmission HPAIHarm Kiezebrink
A comparison between the transmission risk pattern predicted by the model and the pattern observed during the 2003 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.
In this generic overview, you will find the date used in the publication “Modelling the Wind-Borne Spread of Highly Pathogenic Avian Influenza Virus between Farms”, published February 2012 (http://n2gf.com/?p=2377). For the outbreak of avian influenza A(H7N7) in the Netherlands in 2003, much data are available. The overview gives a description of the data used in the analyses of the mentioned publication:
Epidemiological data
There were 5360 poultry farms in the Netherlands in 2003, for all of which geographical information x is available. For 1531 farms the flocks were culled, for all of these the date of culling Tcull is known. For 227 of the 241 infected farms the date of infection tinf has been estimated, based on mortality data. The remaining 14 farms are hobby farms, defined as farms with less than 300 animals, for which no mortality data are available.
The geographic and temporal data together have previously been used to estimate the critical farm density, i.e. above what density of farms outbreaks are can occur.
Genetic data
The HA, NA and PB2 genes of viral samples from 231 farms have previously been sequenced. Sequence data RNA can be found in the GISAID database under accession numbers EPI ISL 68268-68352, EPI ISL 82373-82472 and EPI ISL 83984-84031. These data have previously been used to give general characteristics of the outbreak, to reconstruct the transmission tree and to assess the public health threat due to mutations of the virus in the animal host.
Meteorological data
Available meteorological data include wind speed wv and direction wdir (with a ten degree precision) and the fraction of time r without precipitation for every hour of every day of the outbreak, measured at five weather stations close to the infected farms. These data are available from the Royal Dutch Meteorological Institute at www.knmi.nl.
What would a flu pandemic in the USA look like? More like a war than a natura...Harm Kiezebrink
What would a flu pandemic in the U.S. look like? More like a war than a natural disaster, a government report indicates.
The USA is by far one of the best-prepared countries in the world when it comes to managing possible outbreak situations. This recently declassified Department of Defense report, dated August 2009, estimates that a full-blown flu pandemic could sicken about 30% of the U.S. population, leading to 3 million hospitalizations and 2 million deaths.
This Implementation Plan for Pandemic Influenza of the US Department of Defense directs how to prepare for, detect, respond to and contain the effect of a pandemic on military forces, DOD civilians, DOD contractors, dependents and beneficiaries.
Additionally, it addresses the provision of the US Department Of Defense assistance to civil authorities, foreign and domestic, as well as key security concerns such as humanitarian relief and stabilization operations that may arise.
A very interesting report that you NEED to read!
Lotta Berg 2009 on farm killing poultry at the Nordic Poultry conference in R...Harm Kiezebrink
This document was presented at the Nordic Poultry conference in Reykjavik in November 2009, before the Anoxia method was commercially available.
Dr. Berg compares in this document different methods of emergency killing of poultry, applicable within the Nordic poultry industry (Sweden, Norway, Denmark, Finland and Iceland).
This is the 1st 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 by Anoxiatec Pty for representatives of animal welfare organizations, Australian animal health authorities and the industry and gives an overview of some important practical issues related to Emergency Response, based on my experiences during the outbreak of H7N7 in Holland.
Death caused by hyperthermia. This questionable method has been developed as a last resort option in case of a large-scale outbreak of High Pathogen Avian Influenza in the UK. Even in EU Regulation EU 1099/2009 there is room for countries to use this kind of methods, when compliance is likely to affect human health or significantly slow down the process of eradication of a disease. (EU 1099/2009; article 18, under 3).
Hyperthermia means that the cause of death is overheating the shed of the birds. The normal core body (CB) temperature of a bird must remain within a narrow range around a mean value of 41.4°C if its welfare is to be safeguarded.
If the core body temperature rises above 45°C most poultry will die quickly. To ensure VSD is effective the temperature in the house must rise to 40°C or greater and remain at that level. Maintaining a relative humidity of at least 75% will help speed the onset of death through hyperthermia.
This DEFRA document provides procedures and instructions on using Ventilation Shutdown (VSD) as an emergency method of killing of poultry for disease control purposes.
Nitrogen generation: important new animal welfare applicationHarm Kiezebrink
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 by Anoxiatec Pty for representatives of animal welfare organizations, Australian animal health authorities and the industry gives a general overview of the Anoxia technique.
The Anoxia technique is developed as alternative for existing animal stunning methods that are based on the use of CO2, electrocution, neck dislocation, captive-bolt, as well as killing methods like de-bleeding and maceration.
In the past 10 years, Wageningen University and University of Glasgow conducted several studies that proved that the technique could be applied successfully for culling poultry (Proof of Principle Anoxia Technique). This was the start of the development of several applications based on the Anoxia principle, using high expansion foam filled with >99% Nitrogen that are now introduced for:
1. Stunning and killing of sick and cripple killing piglets less than 5 kg
2. Stunning and killing of sick or cripple poultry (especially poultry > 3kg) who need to be killed on the farm by the staff for welfare purposes (avoiding unnecessary stress or pain)
3. Stunning and killing poultry that arrives on the slaughterhouse but that are unfit to be slaughtered (due to injuries occurred during transportation – providing signs of possible illness etc.)
4. Stunning and killing of male pullets at the hatchery
5. Stunning and killing of half-hatched chickens and embryos in partly-hatched eggs, before destruction
6. Stunning and killing parent stock poultry
7. Killing of animals that has been stunned (captive bolt – blow-on-the-head method, etc.) replacing killing by de-bleeding
8. Culling of ex-layers
9. Culling of poultry for disease control purposes
Last November we started the launch of the commercialization of the Anoxia applications in Holland, Germany and Sweden, focusing on the areas where a solution is most needed: piglets (< 5kg) and poultry (> 3kg) on farms.
Since November 2016, the introduction of these applications took place in Holland, Germany, Sweden and Denmark
OIE animal welfare killing of poultry for disease controlHarm Kiezebrink
In January 2012, the OIE gave in Japan an update on the latest developments in killing animals for disease control purposes. The Anoxia method was one of the presented techniques. Today, one year later, the Anoxia technique is commercially available worldwide. Inhumane killing of animals is not longer necessary and the risks of getting infected has been reduced to a minimum.
Anoxia: High expansion foam
The Anoxia method is unique for creating an environment without oxygen under atmospheric circumstances. High expansion foam is produced by mixing nitrogen and a mixture of water and specially developed high expansion detergent, with an expansion rate upto 1:1000, meaning that 1 litre of water/foam agent mix expands up to 1 m3 foam. Due to the specially designed foam generator, the high expansion foam bubbles are filled with a > 99% concentration of nitrogen. The oxygen level surrounding the animal drops from 21% in atmospheric air to < 1 % once the animal is submerged in the foam.
Anoxia: convulsions, but no stress or pain
The animals need a constant supply of oxygen to the brain. Applying Anoxia foam, the oxygen is replaced by nitrogen. As a result the nitrogen level is raised to > 99% and the oxygen level is lowered to < 1%. Considering the natural reaction to sudden lack of oxygen the animal is rendering quickly into unconsciousness. As a consequence, behavioral indicators like loss of posture and convulsions will appear. With this in mind, unconscious animals are insensitive to perceive unpleasant sensations like pain.
Anoxia: How Anoxia foam is created
A mixture of 97% water and 3% high expansion foam agent is sprayed into the Anoxia foam generator, creating a thin film on the outlet of the generator. At the same time, nitrogen is added with overpressure into the foam generator. The nitrogen expands when it exits the generator, creating robust high expansion foam. The high expansion foam bubbles are filled with > 99% nitrogen.
Anoxia: Single foam generator systems
In practice, one Anoxia foam generator creates a volume of up to 750 liter of high expansion foam per minute. This volume is more than sufficient to fill a wheelie-bin container within 30 seconds. The most common container volumes are: M size - 240 liter; L size - 340 liter; and XL size - 370 liter. The choice of the volume of the container depends of the size of the animal and/or the number of animals that need to be stunned/killed. A lid with a chiffon that seals the container. As soon as the foam exits the chiffon, the gas supply is stopped and the chiffon is closed. The nitrogen gas concentration in the container remains at 99%.
Anoxia presentation during the AI symposium in Taiwan, March 2015Harm Kiezebrink
During the Symposium on managing outbreaks of Avian Influenza in Taiwan, the main subject was managing the outbreaks without breaching animal welfare during the culling operations. Although it seams impossible, this can be done using the Anoxia method (see also www.N2GF.com for more information), under the condition that the entire process is been taking into account: killing of animals, carcass disposal, transport & logistic, Occupational Health & Safety, environmental issues, pest control, contact between animals and humans: all these factors contribute to the risks of spreading. If one factor fails, the virus can escape and infect the next flock, making it needed to kill more birds. For that reason, all factors are equally important to maintain animal welfare during outbreak situations.
In a number of recently published studies, Professor Stegeman (University of Utrecht, Holland) explains that serologic spreading of viruses is related to human contacts with contaminated infected animals, carcasses, manure and materials infected/suspected animals; movements of farm labourers, products, equipment etc. Most of these contacts (and movements) take place prior, during, and after the culling procedure, whereas the quantity and the intensity of the contacts - thus this human contact/materials are decisive factors for the serologic spreading of viruses to enter farms and most likely play an important role in spreading between farms. Suspicion/infection of farm animals inevitably leads to preventive culling of all farm animals within the direct proximity. For that reason, the serologic spread of viruses has become a major animal welfare indicator that has to be taken into consideration as such.
Each culling procedure features its own unique contact pattern between animals and humans and is based on applied culling, disposal and transport technique. These contact patterns related to the specific combination of applied methods, defines the major contribution factors for spreading of infections. Therefore should the potential risks of these procedures be evaluated and rated on the art and the intensity of the potential contact between animals and humans/materials, prior, during and after the procedure.
Therefore, the entire procedure of killing, disposal and transportation is therefore considered as Major Interest, in terms of animal welfare.
This is the 3th 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 by Anoxiatec Pty for representatives of animal welfare organizations, Australian animal health authorities and the industry and gives an overview of more scientific based information on the Anoxia method.
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Hello friends i am BSc Nursing intern.This presentation of mine covers almost each and every aspect related to swine flu.Hope it will help you to increase your knowledge regarding the topic.Looking forward to your feedback.Thank you
Peste des-ruminants-is-a-rinderpest.doc pdfGudyne Wafubwa
Peste des petits ruminant virus (PPRV) is a disease mostly affecting goats and sheep. Since its first discovery, it has caused massive economic loss to most small pastoralists in Africa and other developing countries. It is the integral role of all stakeholders to join hands so as to eradicate the disease.
Avian influenza in herd health and production economicsShareef Ngunguni
Avian influenza is a zoonotic and notifiable disease which occurs world wide. Different risk factors are associated with transmission of the disease to humans. It has two forms HPAI and LPAI. The disease has an impact on public health and economics of the country. In Malawi,it seems the disease appeared in 2005 where it attacked migratory birds
Swine Influenza (swine flu) is a respiratory disease of pigs caused by type A influenza virus that regularly causes outbreaks of influenza in pigs. Swine flu viruses cause high levels of illness and low death rates in pigs. Swine influenza viruses may circulate among swine throughout the year, but most outbreaks occur during the late fall and winter months similar to outbreaks in humans. The classical swine flu virus (an influenza type A H1N1 virus) was first isolated from a pig in 1930.
Similar to The 3 P’s of avian influenza Prevent, Plan, Practice (19)
Low Atmospheric Pressure Stunning is not a humane alternative to Carbon Dioxi...Harm Kiezebrink
I would like express gratitude to the HSA for their 20 years of tireless advocacy for improving pigs' welfare. Their efforts have empowered those seeking alternatives to carbon dioxide stunning. Over nearly 30 years, I've worked on animal welfare friendly stunning applications, particularly regarding stunning/slaughtering using nitrogen foam, and I believe I've found the definitive answer.
The industry originally adopted large-scale carbon dioxide stunning to optimize food production, reduce costs, and lower meat prices, which is only feasible with parallel processing (simultaneously stunning groups of pigs) rather than serial processing (stunning each pig individually). Electrocution is not viable for large-scale operations due to this need for parallel processing. Therefore, a replacement gas that lacks carbon dioxide's detrimental properties is needed, but only a few gases are suitable.
Additionally, the application of an alternative gas must adhere to several fundamental principles:
a) Applicability of the methods for stunning and killing pigs, including their scalability for large-scale application.
b) Description of the technical.
c) Animal welfare consequences associated with specific techniques, including welfare hazards (ABMs), animal-based indicators (ABIs), preventive and corrective measures, and the sufficiency of scientific literature in describing these consequences.
d) Applicability under field conditions.
Introducing a novel application for large-scale pig slaughter is complex and time-consuming before it can be expected, especially given the substantial economic and financial impact for the industry. However, there is hope on the horizon.
The alternative gas is nitrogen, and the application is based on using high-expansion foam filled with 100% nitrogen, applied in a closed container. Within a minute, all air is displaced by the foam, after which the container is sealed, and the foam is broken down with a powerful nitrogen pulse. This ensures that the foam does not affect the stunning process; the entire process can be visually and electronically monitored, and the residual oxygen level in the container is consistently below 2%. The container dimensions are identical to the gondolas used in the globally implemented carbon dioxide gondola system.
The integration of nitrogen foam technology into European regulation EU1099/2009 is nearing completion. All scientific and technical procedures have been submitted to the EU Commission, with finalization awaiting the presentation of EFSA's scientific opinion to the Commission and subsequent approval for inclusion. This final phase is anticipated to occur during the general meeting slated for June 2024.
This marks the first step toward replacing carbon dioxide in 25 years. Fingers crossed for the EU Commission's decision in June 2024!
Harm Kiezebrink
Independent Expert
Preventief ruimen bij vogelgriep in pluimveedichte gebieden en mogelijkheden ...Harm Kiezebrink
New Risk assessment model
The applications designed for farrow-to-weaner pig farms rely on a novel risk assessment model. This model, developed from a recent study, indicates that the likelihood of an undetected infection on nearby farms notably diminishes 7 to 14 days following the identification of the source farm.
This risk assessment model is based a Dutch study that is published by T.J. Hagenaars et al on June 30, 2023: “Preventief ruimen bij vogelgriep in pluimveedichte gebieden en mogelijkheden voor aanvullende bemonstering” (Preventive culling in areas densely populated with poultry, and possibilities for additional sampling).
According to this premise, instead of the standard depopulation approach of euthanizing pigs on-site, pigs beyond the immediate vicinity of infected farms are slaughtered.
Animal Health Canada is currently evaluating new strategies and technologies for managing large-scale emergency situations involving pigs. I have been actively involved in developing strategies and procedures aimed at implementing strict control measures for pig euthanasia during emergencies, with a focus on substantially reducing costs by avoiding unnecessary culling and destruction of healthy animals.
Opting for slaughtering over on-farm euthanasia not only reduces the operational burden on farms but also repurposes the pigs as a valuable protein source rather than considering them as animal waste. This approach assists in crisis management during widespread outbreaks, significantly reduces expenses, and simultaneously mitigates risks.
While this approach is influenced by the new EU regulations implemented since May 2022, it can be adapted for implementation within the context of any EU Member state, as well as in the USA and Canada.
Managing large-scale outbreaks at Farrow-to-Weaner FarmsHarm Kiezebrink
In the face of large-scale outbreaks of swine Influenza A Virus (swIAV), there's a call for exploring various strategies conducive to managing emergencies in field conditions.
Through subdivision, a customized approach can be embraced to enhance operational efficiency and effectiveness while mitigating the impact on individual farms. This tactic maximizes emergency deployment capacity and streamlines standard procedures. Moreover, leveraging the existing capacity of farming aids in alleviating scrutiny on animal welfare standards, presenting a notable advantage.
Nitrogen filled high expansion foam in open ContainersHarm Kiezebrink
On March 31, 2023 the US National Pork Board validated a study by Todd Williams, of Pipestone Veterinary Services, based on the use of high expansion nitrogen foam for the large-scale depopulation of all classes of swine, utilizing Livetec Systems Nitrogen Foam Delivery System (NFDS).
The high expansion foam produced by the Livetec Systems NFDS surrounds the animal in large bubbles filled with nitrogen with a base expansion ration of between 300 and 350 to 1, as mentioned on the information provided by the producer of the firefighting foam.
The Livetec technology, based on using Compressed Air Foam (CAF) filled with nitrogen instead of air for depopulating pigs, emerges within a critical landscape. The complexities of implementing effective emergency depopulation strategies for livestock, particularly swine, present multifaceted challenges. Livetec's approach relies on high expansion firefighting foam, aiming to euthanize pigs by submerging them in foam.
The Livetec system's claims about the effectiveness of nitrogen-filled high expansion foam for depopulating market pigs lack substantial evidence upon analysis. The discrepancy between the actual foam produced during field trials and the promised high expansion foam, coupled with the absence of concrete proof supporting the method's efficacy, discredits the technology's claims.
World bank evaluating the economic consequences of avian influenzaHarm Kiezebrink
Pandemics cause very serious loss of life, restrictions of freedom and serious economic damage. Potential pandemics all are related to our dealing with animals, both wild and domesticated.
In this Word Bank study of 2006, the effects of a severe HPAI pandemic (with a highly pathogenic avian influenza virus crossing the species barrier and infecting humans) predicted economic losses from 2-10% of the world economy.
The economic impact of the present COVID-19 crisis, caused by the SARS-CoV2 virus spreading from wild animals to humans, probably will reach the upper limits of this prediction even if the losses of life might be near the lower limits mentioned in the report (1,4 millions rather than 71 millions).
A common observation is that governments were late to react on the COVID-19 outbreak.
Pandemics are rare, so due to cost-benefit considerations emergency preparations do usually not get beyond an advisory (paperwork) phase. When an emergency eventually arises, the response is too late, too little, and with disastrous effects on animal and/or human welfare that could have been avoided. Relatively small, short-term financial savings result in big, long-term losses.
Protection against outbreaks cannot be achieved by political decisions during a crisis. Our dealing with animals, especially in animal production, must be inherently safe so that animal health and public health are protected.
This is recognized in the One Health strategy that has been adopted internationally.
An outbreak of animal disease occurs should be contained at a very early stage. This can only be realized if all farms have their own emergency plans, with equipment to deal with contagious diseases already present at the farm.
Gas alternatives to carbon dioxide for euthanasia a piglet perspectiveHarm Kiezebrink
The use of nitrous oxide as an anesthetic/euthanasia agent may prove to be affordable, feasible and more humane than other alternatives.
The neonatal stage is a critical time in the life of a pig, when they are prone to become sick or weak. This is the stage at which most euthanasia procedures are required if the pig is judged unable to recover. Any euthanasia method should be humane, practical, economical and socially acceptable to be universally accepted.
They found that nitrous oxide in oxygen appeared to be less aversive than nitrous oxide, nitrogen, or argon all combined with low (30%) concentrations of carbon dioxide or 90% carbon dioxide by itself.
This study is the first to investigate the use of nitrous oxide at sufficiently high concentrations to cause anesthesia. Nitrous oxide, commonly referred to as laughing gas, has been widely used in human surgery and dental offices for its pain-relieving, sedative and anxiolytic effects. It is cheap, non-flammable, non-explosive, legally accessible and not classified as a drug in the U.S., and already commonly used in the food industry as a propellant for food products.
Development of its use into an automated procedure will allow producers to implement it with little effort. Thus its use as an anesthetic/euthanasia agent may prove to be affordable, feasible and more humane than other alternatives.
Although commonly used in other settings, defining animal welfare as part of a corporate CSR setting is not new.
There are many ways to define CSR. What they have in common is that CSR describes how companies manage their business processes to produce an overall positive impact on society. The phenomenon CSR is a value concept that is susceptible to particular ideological and emotional interpretations. Different organizations have framed different definitions - although there is considerable common ground between them.
Some important national players of the food chain at different steps (mainly food retailers and food services) have included animal welfare in their CSR.
World Health Organization director- general Margaret Chan Fung Fu-chun warns bird flu H7N9 is particularly worrying as it could be a flu pandemic strain. This is because H7N9 is unique as it does not make chickens sick but is deadly in humans. Sick birds could usually provide early warning for imminent outbreaks, Chan told The Standard. This comes as Macau reported its first human case of H7N9 yesterday. "The biggest challenge for the world is the next influenza pandemic," Chan said.
Laves presentation practical experiences in the culling of poultry in germanyHarm Kiezebrink
This presentation, based on the practical experiences in culling poultry in Germany, gives an overview of the culling techniques currently in use in Germany. It is presented by dr. Ursula Gerdes, dr. Josef Diekmann and ing. Rainer Thomes.
LAVES is the Lower Saxony State Office for Consumer Protection and Food Safety, located in Oldenburg, Germany. With around 900 employees they are entrusted with tasks in the areas of food and utensil inspection, feed inspection, meat hygiene, veterinary drug monitoring, eradication of animal diseases, disposal of animal by-products, animal welfare, ecological farming, market surveillance and technical process monitoring.
Berg et al. 2014 killing of spent laying hens using co2 in poultry barnsHarm Kiezebrink
September 2015: In Sweden, spent laying hens are killed either by traditional slaughter; on-farm with CO2 in a mobile container combined with a grinder; or with CO2 stable gassing inside the barn. The number of hens killed using the latter method has increased. During these killings a veterinarian is required to be present and report to the Swedish Board of Agriculture.
Data were registered during four commercial killings and extracted from all official veterinary reports at CO2 whole-house killings in 2008–2010. On-farm monitoring showed that temperature decreased greatly and with high variability. The time until birds became unconscious after coming into contact with the gas, based on time until loss of balance, was 3–5 min.
Veterinary reports show that 1.5 million laying hens were killed, in 150 separate instances. The most common non-compliance with legislation was failure to notify the regional animal welfare authorities prior to the killings. Six out of 150 killings were defined as animal welfare failures, eg delivery of insufficient CO2 or failure to seal buildings to achieve adequate gas concentration.
Eleven were either potentially or completely unacceptable from the perspective of animal welfare. We conclude that, on the whole, the CO2 whole-house gas killing of spent hens was carried out in accordance with the appropriate legislation. Death was achieved reliably.
However, there remain several risks to animal welfare and increased knowledge would appear vital in order to limit mistakes related to miscalculations of house volume, improper sealing or premature ventilation turn-off.
The latest outbreak of High Pathogen Avian Influenza in the USA and Canada in the spring of this year and the inability to avoid animal welfare catastrophes ultimately proves that new emergency response strategies are needed. Strategies that are based on taking away the source of infection instead of killing as many animals as possible within 24 hours, regardless the consequences.
The statement that “It’s possible that human infections with these viruses may occur” and that “these viruses have not spread easily to other people” is confusing. Humans can become infected without showing clinical signs. They can become the major carrier of the infection.
Especially during depopulation activities, viruses easily transmit through responders. Tasks like taking layers out of their cages and transport the birds manually through the narrow walkways between the cages, and disposal of infected animals are specific risks that need to be avoided. Simply switching of the electricity so that sick birds don’t have to be handled is not the solution.
Although humans are supposed to be less susceptible, they can become carrier of the virus. Only the highest level of biosecurity could prevent the transmission through the humans and materials that have been in direct contact with infected animals and materials.
Simply switching of the electricity so that sick birds don’t have to be handled is not the solution. Avoid killing animals is always the better option and in Germany, the discussion on the strategy based on neutralizing risks and is in the making. Avoiding situations demands a proactive role of the poultry industry.
Ventilation Shutdown: who takes the responsibility to flip the switch?Harm Kiezebrink
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.
In order to become one step ahead of an outbreak of high pathogen diseases like the current H5N2, the veterinary authorities need to stop the outbreak immediately after the first signals occur. Strict and thorough biosecurity measures are the most fundamental feature to protect poultry flocks on farms.
Without functional culling techniques, the options to effectively and efficiently cull in average more than 925,000 chickens per farm (in Iowa, USA) are limited: either by macerating the chickens alive – or by ventilation shut-down (closing down all ventilation, placing heaters inside the house, and heat the entire house to a temperature higher than 600 C).
Although both methods cause death of the birds, it has not been proven to be effective nor efficient. The primary goal to slowdown outbreaks and bring it to a complete stop but macerating live birds and killing them by heat stress and lack of oxygen would be against all International Animal Welfare standards.
Animal welfare specialists in disease control strongly oppose against the introduction of these most cruel methods of killing poultry and argue that the ban on these methods should be maintained and alternative methods need to be considered.
Avian Influenza in the Netherlands 2003: comparing culling methodsHarm Kiezebrink
During the outbreak of H7N7 in Holland, 29,500.000 birds were killed at the farm. This presentation compares different culling techniques, such as stable gas, container gassing and electrocution.
Reseach on H9N2: evidence that link outbreaks in Eurasia, China, South Korea,...Harm Kiezebrink
In this study, scientists from the U.S. Geological Survey and U.S. Fish and Wildlife Service harnessed a new type of DNA technology to investigate avian influenza viruses in Alaska. Using a “next generation” sequencing approach, which identifies gene sequences of interest more rapidly and more completely than by traditional techniques, scientists identified low pathogenic avian influenza viruses in Alaska that are nearly identical to viruses found in China and South Korea.
The viruses were found in an area of western Alaska that is known to be a hot spot for both American and Eurasian forms of avian influenza.
“Our past research in western Alaska has shown that 70 percent of avian influenza viruses isolated in this area were found to contain genetic material from Eurasia, providing evidence for high levels of intercontinental viral exchange,” said Andy Ramey, a scientist with the USGS Alaska Science Center and lead author of the study. “This is because Asian and North American migratory flyways overlap in western Alaska.”
The new study, led by the USGS, found low pathogenic H9N2 viruses in an Emperor Goose and a Northern Pintail. Both of the H9N2 viruses were nearly identical genetically to viruses found in wild bird samples from Lake Dongting, China and Cheon-su Bay, South Korea.
“These H9N2 viruses are low pathogenic and not known to infect humans, but similar viruses have been implicated in disease outbreaks in domestic poultry in Asia,” said Ramey.
There is no commercial poultry production in western Alaska and highly similar H9N2 virus strains have not been reported in poultry in East Asia or North America, so it is unlikely that agricultural imports influenced this result.
The finding provides evidence for intercontinental movement of intact avian influenza viruses by migratory birds. The USGS recently released a publication about the detection of a novel highly pathogenic H5N8 virus in the U.S. that is highly similar to the Eurasian H5N8 viruses. This suggests that the novel re-assortment may be adapted to certain waterfowl species, enabling it to survive long migrations. That virus, and associated strains, have now spread from early detections in wild and domestic birds in Pacific states to poultry outbreaks in Minnesota, Missouri and Arkansas.
“The frequency of inter-hemispheric dispersal events of avian influenza viruses by migratory birds may be higher than previously recognized,” said Ramey.
While some of the samples for the project came from bird fecal samples collected from beaches at Izembek National Wildlife Refuge, most of the samples came from sport hunters.
“For the past several years, we’ve worked closely with sport hunters in the fall to obtain swab samples from birds and that has really informed our understanding of wildlife disease in this area,” said Bruce Casler, formerly a biologist with the USFWS Izembek National Wildlife Refuge and a co-author of the study. Non
Risk analysis on the role of wild ducks by the introduction of Avian Influenz...Harm Kiezebrink
Lelystad, April 2015: According to a recently published study (in Dutch) by the University of Wageningen, wild ducks are are identified as a high risk factor for the introduction of Low Pathogen Avian Influenza viruses in free-range laying hens.
Through a case-control study investigated presumed risk factors for introduction of low-pathogenic avian influenza (LPAI) virus in poultry laying farms free range. Under a LPAI virus was defined in this study: an avian influenza virus of each subtype (H1 H16 tm), with the exception of the highly pathogenic avian influenza (HPAI) viruses.
In order to determin the potential risk factors for infection with LPAI virus, forty Dutch free range poultry farms where the introduction of Low Pathogen Avian Ifluenza virus has been confirmed in the past (cases) were compared with 81 free range poultry farms where no introduction has taken place (controls). Questions about the presence of potential risk factors through surveys submitted to the poultry farmers.
The analysis of the various factors shows that the risk of introduction of LPAI virus on free range laying farms 3.3 (95% CI: 1.2-9.7) times higher as mallards has identified by the farmer entering the free range area at least once a week, in comparison to free-range laying farms where wild ducks have been identified by the farmer once a month or less.
It seems logical that the regular presence of wild ducks in the free-range increases the risk exposure of the chickens LPAI virus since wild waterfowl are the natural reservoir of avian influenza viruses.
The study also revealed that the risk factor for free range layer farms located on clay is 5.8 (95% CI: 2.2-15.1) times have higher risk of introduction of LPAI virus then free range layer farms on sandy soil or a soil other than clay. The soil on which the free range farm is situated is probably an indirect risk factor (association and not causation): especially in case the farm is located near the coast or close to rivers.
OIE terrestrial code killing of animals for disease preventionHarm Kiezebrink
The guidelines are intended to help countries identify priorities, objectives and the desired goal of disease control programmes.
Disease control programmes are often established with the aim of eventual eradication of agents at a country, zone or compartment level. While this approach is desirable, the needs of stakeholders may require a broader range of outcomes.
For some diseases, eradication may not be economically or practically feasible and options for sustained mitigation of disease impacts may be needed.
Accelerate your Kubernetes clusters with Varnish CachingThijs Feryn
A presentation about the usage and availability of Varnish on Kubernetes. This talk explores the capabilities of Varnish caching and shows how to use the Varnish Helm chart to deploy it to Kubernetes.
This presentation was delivered at K8SUG Singapore. See https://feryn.eu/presentations/accelerate-your-kubernetes-clusters-with-varnish-caching-k8sug-singapore-28-2024 for more details.
Epistemic Interaction - tuning interfaces to provide information for AI supportAlan Dix
Paper presented at SYNERGY workshop at AVI 2024, Genoa, Italy. 3rd June 2024
https://alandix.com/academic/papers/synergy2024-epistemic/
As machine learning integrates deeper into human-computer interactions, the concept of epistemic interaction emerges, aiming to refine these interactions to enhance system adaptability. This approach encourages minor, intentional adjustments in user behaviour to enrich the data available for system learning. This paper introduces epistemic interaction within the context of human-system communication, illustrating how deliberate interaction design can improve system understanding and adaptation. Through concrete examples, we demonstrate the potential of epistemic interaction to significantly advance human-computer interaction by leveraging intuitive human communication strategies to inform system design and functionality, offering a novel pathway for enriching user-system engagements.
Neuro-symbolic is not enough, we need neuro-*semantic*Frank van Harmelen
Neuro-symbolic (NeSy) AI is on the rise. However, simply machine learning on just any symbolic structure is not sufficient to really harvest the gains of NeSy. These will only be gained when the symbolic structures have an actual semantics. I give an operational definition of semantics as “predictable inference”.
All of this illustrated with link prediction over knowledge graphs, but the argument is general.
State of ICS and IoT Cyber Threat Landscape Report 2024 previewPrayukth K V
The IoT and OT threat landscape report has been prepared by the Threat Research Team at Sectrio using data from Sectrio, cyber threat intelligence farming facilities spread across over 85 cities around the world. In addition, Sectrio also runs AI-based advanced threat and payload engagement facilities that serve as sinks to attract and engage sophisticated threat actors, and newer malware including new variants and latent threats that are at an earlier stage of development.
The latest edition of the OT/ICS and IoT security Threat Landscape Report 2024 also covers:
State of global ICS asset and network exposure
Sectoral targets and attacks as well as the cost of ransom
Global APT activity, AI usage, actor and tactic profiles, and implications
Rise in volumes of AI-powered cyberattacks
Major cyber events in 2024
Malware and malicious payload trends
Cyberattack types and targets
Vulnerability exploit attempts on CVEs
Attacks on counties – USA
Expansion of bot farms – how, where, and why
In-depth analysis of the cyber threat landscape across North America, South America, Europe, APAC, and the Middle East
Why are attacks on smart factories rising?
Cyber risk predictions
Axis of attacks – Europe
Systemic attacks in the Middle East
Download the full report from here:
https://sectrio.com/resources/ot-threat-landscape-reports/sectrio-releases-ot-ics-and-iot-security-threat-landscape-report-2024/
GDG Cloud Southlake #33: Boule & Rebala: Effective AppSec in SDLC using Deplo...James Anderson
Effective Application Security in Software Delivery lifecycle using Deployment Firewall and DBOM
The modern software delivery process (or the CI/CD process) includes many tools, distributed teams, open-source code, and cloud platforms. Constant focus on speed to release software to market, along with the traditional slow and manual security checks has caused gaps in continuous security as an important piece in the software supply chain. Today organizations feel more susceptible to external and internal cyber threats due to the vast attack surface in their applications supply chain and the lack of end-to-end governance and risk management.
The software team must secure its software delivery process to avoid vulnerability and security breaches. This needs to be achieved with existing tool chains and without extensive rework of the delivery processes. This talk will present strategies and techniques for providing visibility into the true risk of the existing vulnerabilities, preventing the introduction of security issues in the software, resolving vulnerabilities in production environments quickly, and capturing the deployment bill of materials (DBOM).
Speakers:
Bob Boule
Robert Boule is a technology enthusiast with PASSION for technology and making things work along with a knack for helping others understand how things work. He comes with around 20 years of solution engineering experience in application security, software continuous delivery, and SaaS platforms. He is known for his dynamic presentations in CI/CD and application security integrated in software delivery lifecycle.
Gopinath Rebala
Gopinath Rebala is the CTO of OpsMx, where he has overall responsibility for the machine learning and data processing architectures for Secure Software Delivery. Gopi also has a strong connection with our customers, leading design and architecture for strategic implementations. Gopi is a frequent speaker and well-known leader in continuous delivery and integrating security into software delivery.
Connector Corner: Automate dynamic content and events by pushing a buttonDianaGray10
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Create a campaign using Mailchimp with merge tags/fields
Send an interactive Slack channel message (using buttons)
Have the message received by managers and peers along with a test email for review
But there’s more:
In a second workflow supporting the same use case, you’ll see:
Your campaign sent to target colleagues for approval
If the “Approve” button is clicked, a Jira/Zendesk ticket is created for the marketing design team
But—if the “Reject” button is pushed, colleagues will be alerted via Slack message
Join us to learn more about this new, human-in-the-loop capability, brought to you by Integration Service connectors.
And...
Speakers:
Akshay Agnihotri, Product Manager
Charlie Greenberg, Host
Essentials of Automations: Optimizing FME Workflows with ParametersSafe Software
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Join us for an insightful dive into the world of FME parameters, a critical element in optimizing workflow efficiency. This webinar marks the beginning of our three-part “Essentials of Automation” series. This first webinar is designed to equip you with the knowledge and skills to utilize parameters effectively: enhancing the flexibility, maintainability, and user control of your FME projects.
Here’s what you’ll gain:
- Essentials of FME Parameters: Understand the pivotal role of parameters, including Reader/Writer, Transformer, User, and FME Flow categories. Discover how they are the key to unlocking automation and optimization within your workflows.
- Practical Applications in FME Form: Delve into key user parameter types including choice, connections, and file URLs. Allow users to control how a workflow runs, making your workflows more reusable. Learn to import values and deliver the best user experience for your workflows while enhancing accuracy.
- Optimization Strategies in FME Flow: Explore the creation and strategic deployment of parameters in FME Flow, including the use of deployment and geometry parameters, to maximize workflow efficiency.
- Pro Tips for Success: Gain insights on parameterizing connections and leveraging new features like Conditional Visibility for clarity and simplicity.
We’ll wrap up with a glimpse into future webinars, followed by a Q&A session to address your specific questions surrounding this topic.
Don’t miss this opportunity to elevate your FME expertise and drive your projects to new heights of efficiency.
Dev Dives: Train smarter, not harder – active learning and UiPath LLMs for do...UiPathCommunity
💥 Speed, accuracy, and scaling – discover the superpowers of GenAI in action with UiPath Document Understanding and Communications Mining™:
See how to accelerate model training and optimize model performance with active learning
Learn about the latest enhancements to out-of-the-box document processing – with little to no training required
Get an exclusive demo of the new family of UiPath LLMs – GenAI models specialized for processing different types of documents and messages
This is a hands-on session specifically designed for automation developers and AI enthusiasts seeking to enhance their knowledge in leveraging the latest intelligent document processing capabilities offered by UiPath.
Speakers:
👨🏫 Andras Palfi, Senior Product Manager, UiPath
👩🏫 Lenka Dulovicova, Product Program Manager, UiPath
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Smart TV Buyer Insights Survey 2024 by 91mobiles.pdf91mobiles
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Link to video recording: https://bnctechforum.ca/sessions/selling-digital-books-in-2024-insights-from-industry-leaders/
Presented by BookNet Canada on May 28, 2024, with support from the Department of Canadian Heritage.
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The 3 P’s of avian influenza Prevent, Plan, Practice
1. The 3 P’s of Avian Influenza:
Prevent, Plan, Practice 1
Is There a Monster in the
(Poultry) House? 2
AI Outbreak in Europe in 2003:
Lessons to Be Learned 4
Depopulation of Poultry Flocks
during Disease Outbreaks
and Other Catastrophic Events 9
Disposal Options for Avian
Influenza Flocks 10
Spring 2006 Volume 7, Number 1
Editor’s Note
The 3 P’s of Avian Influenza: Prevent,
Plan, Practice
These days everyone from the poultry industry wonders what may be heading
our way as birds start their migratory flight north to their breeding grounds.
Will this time bring the undesired virus? We cannot stop wild birds from flying
and carrying viruses with them, including AI. However, there are a few things
we can do that can be summarized as the 3 P’s of Avian Influenza: Prevent,
Plan, and Practice. Prevent any contact of wild birds with poultry and apply
very strict biosecurity measures to reduce the chances of an outbreak. Do not
wait until an outbreak occurs; establish a clear plan of action beforehand when
See 3 P’s on page 2
is published by the College of Agriculture and Natural Resources,
University of Maryland, College Park, Maryland.
EDITORS
Inma Estevez, Ph.D.
Roselina Angel, Ph.D.
Dept. of Animal and Avian Sciences
University of Maryland
College Park, MD 20742
HOW TO CONTACT US
Inma Estevez, Ph.D.
E-mail: iestevez@umd.edu
Tel: 301-405-5779
Fax: 301-314-9059
Roselina Angel, Ph.D.
E-mail: rangel@umd.edu
Tel: 301-405-8494
Fax: 301-314-9059
CONTRIBUTORS
Daniel R. Perez, PhD.
Assistant Professor
Department of Veterinary Medicine
University of Maryland, College Park
dperez@umd.edu
Harm Kiezebrink
Independent Expert in the Control of
Avian Influenza at the Farm Level
Adcare GmbH (Munich, Germany),
center@ad-care.com
Dr. Nathaniel L. Tablante
Extension Poultry Veterinarian
University of Maryland, College Park
nlt@umd.edu
Bud Malone
Extension Poultry Specialist
University of Delaware
malone@udel.edu
In This Issue
2. 2
you have time to think and design
the best strategies for effective con-
trol. And practice! Make sure you
have the opportunity to do a mock
trial to determine the effectiveness
of your plan of control. This issue of
Poultry Perspectives offers informa-
tion that can be used to comply with
the 3 P’s.
There is never going to be a better
time to work on a plan than RIGHT
NOW!
3 P’s from page 1
For the past year or so, the media
has flooded newspapers, radio and
television shows, and the Internet
with the fear that a new influenza
pandemic is looming over us. Is that
fear founded? When will the pan-
demic occur? I work with poultry all
the time—am I at risk of becoming
infected and dying? What can we
do to protect our poultry and our-
selves from the effects of this virus?
I will go over these questions in the
context of poultry avian species:
there are approaches that are easy to
implement and can stop the spread
of these viruses that can infect
people. I must point out, however,
that potentially pandemic strains
will continue to emerge from wild-
life avian hosts. The best weapon
we have to control the emergence
of these viruses is to adopt strict bio-
security measures, implement good
surveillance strategies, and learn
more about the risks of the disease
for animals and humans.
Avian influenza is a disease of
poultry, whose disease symptoms
vary from completely mild or
unnoticeable to a catastrophic
disease with a mortality rate that
can reach up to 100 percent in
some avian species. The natural
hosts of the virus are ducks,
shorebirds, and other species of wild
aquatic birds. In the natural hosts,
influenza infections cause almost
no disease signs and the infection is
established mostly in the intestinal
tract. The virus is excreted with
the feces into the water, promoting
a cycle of fecal-oral transmission.
Occasionally, the virus “jumps”
from wild birds to domestic
birds causing disease outbreaks
(sometimes briefly subclinical, and
then becoming more obvious as the
disease increases in virulence).
The surface of the virus contains
two major components, which are
the targets of antibodies generated
by the host’s immune system.
These two components are divided
into subtypes based on the ability
of antibodies to recognize them.
There are 16 subtypes of one of
the components known as HA or
hemagglutinin and 9 subtypes of
the other component, known as
NA or neuraminidase. Thus, the
nomenclature of influenza viruses
includes the subtype characteristics
of the virus. For example, the H5N1
viruses in Asia contain an HA of
subtype 5 and an NA of subtype
1. Both components are essential
for the survival of the virus, and
antibodies created against the HA
can prevent the virus from infecting
the cell.
In addition, influenza viruses
are named based on characteristics
of the host, the place of isolation,
some form of strain identification
code, and the last two digits of
the year of isolation. For example,
A/chicken/Hong Kong/YU562/01
(H5N1) is a type A H5N1 influenza
virus (all avian influenza viruses are
type A viruses; humans are affected
by types A and B), isolated from a
chicken in Hong Kong in 2001 and
identified as YU562. Because the
genome of influenza viruses is made
up by segments and co-infections in
birds are common, influenza viruses
with many different combinations
of HA and NA subtypes have been
isolated in nature. Only viruses of
the H5 and H7 subtypes are known
to cause high mortality in birds. All
other virus subtypes cause a milder
Is There a Monster in the (Poultry) House?
by Daniel R. Perez, PhD.
3. 3
form of disease affecting either the
intestinal or respiratory tracts, or
both.
Signs of disease may include
excess mucus, diarrhea, watery eyes,
and drops in egg production. The
more virulent forms of the disease
are accompanied by neurological
disorders and massive hemorrhages,
which are clearly noticeable as a
purple coloration on the combs and
feet. The time course of the infection
also varies greatly from a few days
to a sudden disease that kills the
birds in less than a day.
Accumulation of specific
mutations on the HA of the H5
and H7 subtypes results in the
emergence of strains with high
virulence and mortality; however,
mortality rates can vary greatly
among different avian species,
with the most frequently affected
being chickens and turkeys. It is not
known exactly which avian species
contribute to the emergence of these
highly pathogenic strains, although
both chickens and turkeys seem to
play a major role. Many disease
outbreaks in chickens and turkeys
have started with H5 or H7 subtypes
that were very mild, that sometimes
went undetected and later became
highly virulent.
Because many other intestinal or
respiratory diseases of poultry can
cause similar disease symptoms, we
cannot rely on disease symptoms
alone to diagnose avian influenza.
Thus, constant monitoring of the
flock is encouraged by submitting
serum, tracheal and cloacal swabs to
the diagnostic laboratory to perform
antibody tests and virus isolations.
The mild forms of the disease may
last only a few days, leaving only
a small window of opportunity to
detect the virus. Serum samples
should also be collected to analyze
the presence of antibodies against
the virus, which last much longer
and are easier to detect.
Several diagnostic companies are
developing tests that will allow the
detection of the virus or antibodies
to it at the farm level. These tests
are easy to use and very sensitive
and are currently pending USDA
approval. A word of caution must
be used here: If the test is positive,
it is most likely that avian influenza
is present in your flock; however,
the test will not indicate what HA
or NA subtype it is. A reliable
diagnostic laboratory test must be
performed to confirm the presence
and characteristics of the virus. On
the other hand, a negative test at the
farm level does not guarantee that
the flock is free of avian influenza.
Submission of samples to the lab
is strongly encouraged, even when
the flock appears perfectly healthy.
Making a habit of screening for
potential disease signs, excess
an Avian influenza virus from wild
birds are very low. Infection with
some viruses may be very localized
and not life-threatening: H7
infections, for example, can cause
conjunctivitis (pink eye) in humans.
Avian influenza viruses that become
adapted to domestic flocks are also
not likely to “jump” to humans.
However, the experience in Asia
has taught us that letting influenza
viruses circulate in domestic bird
species for extended periods can
lead to strains that become more
and more efficient at making the
“jump” to humans and other animal
species. Once again, being vigilant,
identifying potential disease signs,
and practicing strict biosecurity
measures provide greater protection
for you and your flock. The Animal
and Plant Health and Inspection
Services (APHIS) has an excellent
online resource called Biosecurity
for the Birds (http://www.aphis.
usda.gov/vs/birdbiosecurity/), which
provides extensive information about
biosecurity and other strategies for
protecting your flock and yourself.
You can also contact APHIS at toll-
free 1-866-536-7593. Additional
information about avian influenza
can be found at http://www.agnr.
umd.edu/aicap, which provides
information about the disease,
contains several educational
resources, and presents an overview
of several research projects currently
funded by the USDA on prevention
and control of avian influenza in
the U.S. (a newly updated version
of this web resource is expected by
mid-November).
The current H5N1 situation has
sounded the alarm in animal and
public health organizations at the
international and national levels.
The World Health Organization
speculates that it will take at least
two years before H5N1 viruses
are controlled in Asia. The list of
countries reporting outbreaks of
H5N1 HPAI continues to increase
despite the 160 million domestic
poultry that have died or been
culled in Asia to control the spread
of the disease. The estimated
“Because many other
intestinal or respiratory
diseases of poultry
can cause similar
disease symptoms,
we cannot rely on
disease symptoms alone
to diagnose Avian
Influenza.”
mortality, and taking samples for
laboratory analysis will achieve two
purposes: Both you and your flock
will be protected from spreading a
disease that can carry major animal
and public health implications.
Remember, not reporting the
presence of the virus in your flock
will most likely backfire on you.
Sooner or later, you and your flock
will be severely affected.
Am I and those in contact with
chickens and their products at risk
of becoming infected? Most avian
influenza viruses, regardless of the
subtype, do not infect humans. Avian
influenza viruses from wild birds are
so adapted to them that the chances
of humans becoming infected with
4. 44
economic losses to the Asian poultry
sector are approximately $10
billion, threatening the livelihood
of millions of people. Recent
findings suggested that migratory
aquatic birds might facilitate the
transmission of the H5N1 viruses,
and recent reports indicating the
presence of the virus in several
countries in Europe have confirmed
this assumption. Importation of
exotic birds is another way of
spreading the disease as the virus
has recently been reported in the
United Kingdom in imported birds.
There has to be a major effort
worldwide to strictly control the
movement of exotic birds between
countries, not only to control the
spread of avian influenza, but also
other known or unknown diseases.
Is the U.S. vulnerable? Imported
birds are strictly quarantined and
tested before they are allowed to
enter the U.S., so in this regard
the U.S. is protected. The U.S.
does not allow importation of live
commercial birds from Asia and
similar measures have been quickly
adopted for countries reporting avian
influenza. However, the virus could
potentially enter the U.S. through
migratory birds, smuggling of birds,
or through people. Keep your birds
in the house and do not let them
co-mingle with wild birds. Control
the access of other animal pests into
the poultry house. Do not let anyone
you do not know come close to your
poultry house.
Are these fears founded?
Absolutely. The fact that the virus
has managed to cross to humans
several times with significant
mortality and that all human
influenza pandemics have initiated
from an avian influenza virus,
put H5N1 viruses in the list of
potentially pandemic viruses. When
will the H5N1 pandemic occur? We
do not know. It may start tomorrow
or it may not happen in our lifetime;
however, we do need to be prepared
because a pandemic influenza
virus can emerge at any time. If the
previous 100 years gave us three
pandemics, how many are we going
to get in the next 100 years? As the
world prepares for the inevitable,
poultry farmers around the world
can be at the forefront in the control
of the disease and, thus, prevent the
emergence of pandemic influenza
strains at the amplification stage:
poultry species. In the research
arena, novel vaccine strategies and
faster and more sensitive diagnostic
tools will soon provide a number of
alternatives for the poultry sector to
combat the disease. In the future,
researchers will be able to predict
which viruses are more likely to be a
pandemic threat. However, it is only
going to be through the combined
efforts of poultry farmers, poultry
veterinarians, government agencies,
diagnosticians, and researchers that
the inevitable be made preventable.
AI Outbreak in Europe in 2003: Lessons to Be Learned
by Harm Kiezebrink
Introduction
In October 1997 the poultry world
was shocked by the news that avian
influenza (AI) had struck Asia for
the first time in decades. In Hong
Kong all poultry was culled within
days and the outbreak seemed to be
under control. But as we know now,
it did not disappear. The same H5N1
virus is currently rushing with dev-
astating force over the globe. Many
experts and governments tried to
warn about the necessity of control-
ling the disease to avoid potential
catastrophic consequences without
success. It is time to come back to
reality and stick to the facts, espe-
cially when it comes to preparing
the poultry industry for a possible
outbreak.
5. 5
Consequences for the
Industry
Avian influenza is not solely
a chicken disease. AI can also
affect other bird species as well as
humans. Nevertheless, the threat of
humans contracting AI has always
been shown to be directly linked to
poultry and the poultry industry.
This connection can be extremely
devastating for the industry, as
poultry consumption drops after
the appearance of AI. I will give an
example that shocked the farming
industry in Holland. A Dutch
animal welfare activist group who
are opposed to the commercial
poultry industry misused the link
between avian influenza and the
pandemic threat to human health
in a public campaign against the
poultry industry. In December 2005
the Dutch animal welfare activist
group, ‘Wakker dier’, began to
exploit general public fear about
the human implications of AI by
broadcasting a totally misleading
radio commercial with the slogan
“Slow down the virus, don’t eat
chicken.” Poultry farmers reacted
quickly, asking a judge to stop this
campaign immediately, but without
any success. In spite of poultry
producers’ arguments that AI in Asia
and Europe occurred only within
wildfowl and backyard farming and
that the ‘Wakker dier’ campaign was
based upon fragmented information
pulled out of context, the judge
concluded that ‘Wakker dier’ gave
sufficient “facts to justify” their
campaign. The judge rejected the
arguments and demands from the
poultry industry. The disintegrating
Dutch farming industry now faced
an unexpected drop in poultry
products just a few days before
Christmas.
How the Truth Became
So Distorted
News agencies start their reports
with this statement or one similar:
“Today it was confirmed that the
virus H5N1, the deadly virus that
under certain circumstances can
affect humans, has been found in
a population of migrating ducks.
The export of all poultry products
is directly banned.” I have heard
these sentences over and over again,
especially in the last couple of
weeks. The consequences are clear.
The public links the outbreak of
avian influenza directly to poultry,
because of the ban on poultry
products. As a consequence, the
consumption of poultry has dropped
dramatically. In Romania, for
example, poultry consumption has
been reduced by 60 percent due
to media reports. When the public
panics the first victim is the poultry
industry. In a competitive market,
the poultry industry has a lot to
their own birds and they should
avoid contact with poultry products
coming from poultry that is not
slaughtered by the poultry industry.
Avian influenza is closely
connected to the poultry industry in
the public’s mind because AI can
spread via chickens that have come
in contact with the virus. This is
true not only in free range farming,
but also in backyard farming and
with fighting cocks. Therefore, it is
important to explain to the public that
they have to avoid all unnecessary
contact with poultry, wild fowl, and
domestic birds in order to prevent the
virus jumping to humans.
Lessons Learned
The Dutch poultry industry and
Dutch government learned a very
important lesson during the 2003
AI crisis in Europe. As a result,
all farms in the Netherlands are
inspected for AI once a year; all free
range farms are inspected four times
per year and during the migration
season, all free range poultry have
to be kept inside or under a net. The
costs for this operation were covered
by the farmers themselves. From this
crisis, several lessons can be learned
and applied to the poultry industry
in the U.S.
Lesson One: Be Prepared!
Why did the Dutch farmers accept
such a drastic measure and such
high costs? Because they had to
survive the financial consequences
of the first major outbreak in 2003.
Unprepared and neglecting their
own responsibility, they trusted the
government to take care of the crisis.
They felt that if a disaster struck,
the government would act and they
would not have to worry.
Now, after the experience of
2003, the farmers know better.
Now they know they have to play
an active role in surveillance and
biosecurity programs, but that
was not the case in 2003. At that
time, the farmers only thought in
terms of financial compensation
“The consequences
are clear. The public
links the outbreak of
Avian Influenza directly
to poultry, because
of the ban on poultry
products.”
lose and the best strategy to control
potential negative effects of AI is to
be open with the public. It is in the
best interests of the poultry industry
to launch a campaign to show that
the industry does everything it can
to prevent an outbreak and also that
the industry takes animal welfare
issues seriously.
Informing the Public
As the Dutch example shows, the
industry should take communication
about the consequences of avian
influenza seriously. They should
explain to the public and their
customers that it is perfectly safe to
eat poultry products as long as the
product is coming out of the grocery
store. People should not slaughter
6. 6
and relied on their assumption
that the government would take
care of them. After all, there were
funds created to cover the direct
costs: European Community (EC)
funds covered 50% of the direct
costs; local government covered
25%; and farmers’ funds (created
by the farmers organizations
themselves) covered 25%. What
the Dutch poultry industry learned
from the 2003 crisis is that it is far
more important to think in terms
of preparedness than in terms of
financial cost.
In 2003 the Dutch government
prepared for an AI outbreak based
on wrong assumptions. The Dutch
contingency plan in 2003 for an AI
outbreak was not successful because
it was based on an obsolete culling
method. The contingency plan
was still based on the use of HCN,
although another European Union
(EU) law forbids this type of nerve
gas. HCN is listed as a potential
weapon of mass destruction. The
services in charge ignored this fact
and the plan could not be carried
out. The fact that Holland was not
prepared with a well thought out
plan was the main reason for the
huge impact of the 2003 crisis. And
because of the great number of
affected farmers, the funds created
by the farmers’ organization dried
up the first week of the outbreak!
Take Holland as an Example
I don’t know exactly why, but
I am pretty well convinced that
unpreparedness is still too common
for most industries and governments.
False hopes and a reluctant
government are the best ingredients
for a future financial disaster. Here
are some facts and figures from
2003:
• In February 2003 the crisis
struck in Barneveld, the
heart of the Dutch poultry
industry. The R0 factor, the
reproduction factor, was 8.
That meant that one infected
farm was the source of
infection at 8 other farms.
• In total, 1,200 farms were
cleared and almost 32 million
birds were culled.
• Thirty-three percent of
all farms in Holland were
involved.
• The outbreak was stopped
within 10 weeks.
• On a 24/7 basis, more than
3,000 people were involved in
fighting the disease, culling
animals, and controlling the
operations.
• Total direct costs were
approximately 376 million
Euros; the uninsured indirect
costs were 1 billion Euros.
• 84 people were directly
infected with the virus and
they infected approximately
8,500 other people among
their families, friends, and
relatives.
There is a pattern that signals
things to come and we in Holland
started to understand this pattern:
• Migrating birds enter border
and mix with stationary birds,
most of the time in wetland
areas.
• Dead wild birds are found
and examined.
• Confirmation of avian
influenza.
These are the first signs,
signalling that procedures have to
be put in place to keep the virus
within the wildfowl population and
in a restricted area. The following
immediate actions have to be taken:
• Completely halt the transport
of birds and other animals.
• Control borders in the region.
• Ban fishing and hunting to
keep people out of the area as
much as possible.
• Rigorously cull all poultry in
the infected area, in an area
of about 1.5 miles around the
source of the outbreak.
• Daily sampling and
inspection.
• Reduce the number of people
entering the zone, especially
the press.
• Vaccinate against human flu
all farmers, veterinarians, and
poultry industry workers as
well as the general population
working or living within
the zone.
• Keep all domestic livestock
in barns.
• Prepare a ring vaccination
plan for poultry around the
infected zone.
Lesson Three: Protection Starts
with Proper Planning
This is the signal for the industry
to maximize efforts to protect
their farms, their employees, and
their families. This means that
each farm should work on an
individual contingency plan on a
“In 2003 the Dutch
government prepared for
an AI outbreak based on
wrong assumptions.”
• Unfortunately, 1 veterinarian
died.
• After one year, 25% of
the entire industry had not
survived.
As a note, Holland had to deal
with the lesser pathogen, H7N7
virus. If this had been the H5N1
version, the consequences would
have been much worse.
Lesson Two:Adequate Response
Looking at the facts above, it
seems that scientists are largely
concerned that governments as
well as the poultry industry are
not prepared for a crisis of this
magnitude.
7. 7
farm level, on a regional level, and
on a countrywide level. This will
help to keep a possible outbreak
within the industry as localized
as possible. The jump of the virus
itself into the industry can hardly
be prevented but, with a little luck,
these efforts will help to minimize
the consequences. Someone wisely
compared preparedness with ‘having
oil in your lamp when you know
darkness is coming.’
Lesson Four: Safety Before
Animal Welfare
One thing I have learned from
my experience in the field is that
safety of the operators has to be
maximized. New techniques are
needed to minimize the number of
operators needed and to guarantee
that animals are culled in the most
humane manner. This is a tough
job and not very rewarding, but
is absolutely vital to prevent a
pandemic through the operators. It is
quite simple. Technically speaking,
culling animals can never be done
in an animal welfare friendly way.
In spite of all efforts to choose the
best possible culling option, the
technique is only a small part of the
operation. It is largely in the hands
of those who carry it out and control
the culling operation. These people
include cullers, veterinarians, and
governmental officials in the field
who carry out the responsibility
for the operations. It is never the
scientists, animal welfare people,
or politicians who risk their lives
by going in the infected areas.
Animal welfare is a very important
responsibility, but stopping the
spread of the disease must always
be the highest priority. By stopping
the spread of the disease, the lives
of millions of animals can be saved.
However, in the aftermath of a
crisis, those who were responsible
for the culling operations are always
the first to be blamed for the killing
of innocent animals.
Lesson Five: Manage the Chain
When it comes to responsibility
to prevent an outbreak, a ‘hobby
farmer’ with a stock of five birds in
his backyard is just as responsible
as a broiler farmer with a stock of 1
million birds. The difference lies in
the details, but everything possible
has to be done to prevent the spread
of the virus.
Lesson Six:The Method of Choice
The most appropriate culling
method for the backyard farmer
may be totally different from that
of the commercial farmer. But for
all categories of farming, dedicated
methods have to be in place before a
possible outbreak. The best methods
are:
• Gas bags. An improvement
on this method is the
use of bags made out of
biodegradable plastic that are
put into dustbins. The bags
are first filled with at least
60% carbon dioxide before
being filled with animals. The
pre-filling renders the animals
unconscious before they die,
so they do not suffer. The
animals are stunned within 30
seconds and die within one
minute. The bags, together
with some manure, are then
landfilled above groundwater
level. After one year, the
bag is gone, together with
the birds and the virus. This
flexible and effective low cost
method is the preferred way
to cull small flocks (up to
1,000 birds).
• Container systems. There
are three types of containers
in use in Holland: small 340
litre bins, 1.100 litre wheelie
bins, and 20 foot container.
The most widely used size is
8. 8
the 1,100 litre container. All
systems work on the same
principle: first the containers
are filled up with a minimum
of 60% carbon dioxide before
the animals are put in. As with
the gas bags, the birds are
culled within 30 seconds and
killed within one minute. This
method is mostly used for
layer hens in cages, because
the animals have to be taken
out of their cages anyway.
• Electrocution. The fourth
method is the use of a
mobile electrocution line,
similar to what is used in
slaughterhouses, but with a
much higher electric current.
The birds are killed within
a fraction of a second and
therefore this is the preferred
method from an animal
welfare point of view. A
negative aspect of this method
is that the animals have to
hang upside down before they
are killed. This technique can
generally be used for all types
of animals including broilers,
layer hens, turkeys, geese, and
ducks. This technique is often
used if the fifth method, stable
gassing, failed.
• House gassing. Carbon
dioxide gas is pumped under
pressure into a house with
broilers, parent stock, and
young turkeys. This method
only works if the stable
can be sealed off, keeping
sufficient space for the air
in the stable to escape at the
moment the carbon dioxide
is pumped in. It takes 30
minutes to one hour until the
birds die. From an animal
welfare point of view, it is
better to choose a method that
leads to a quicker death, but
when the quantity of birds per
house is large, there are not
many alternatives. This is the
method of choice in Europe
for culling large quantities of
birds, especially broilers. It
is important to keep in mind
that in Holland, the house
gas method could only be
practiced when the house was
suitable for this method, as
was the case in 33% of Dutch
houses. That means that 67%
of all the houses in Holland
were not suitable candidates
for the use of the preferred
gassing method, due to the
type of housing or to the type
of animal (ducks, layer hens,
turkeys, very young birds).
So even though house gassing
was the preferred method,
67% of all the farms had to
use a variety of other culling
methods.
carcasses were put into air- and
watertight containers and transported
by truck to the rendering plant. The
maximum rendering capacity was
250 tons per day with a limited
number of vehicles to transport the
dead animals to the rendering plants.
Despite the risk that transporting
diseased birds could cause further
spread of the disease, there were
few other options available at that
time. Landfill in Holland is nearly
impossible, because we live below
sea level, so the risk of the virus
touching groundwater level was too
high and house fermentation had not
been developed at that time.
Conclusion: Start
Yesterday
It is important to go back to
common sense and stay with the
facts. There is no reason to panic
yet. However, only a few countries
have the necessary action plan to
control an outbreak in the first 24
hours after it is confirmed. At the
moment there are few specialists
working in this field worldwide who
sell or rent the culling equipment
described above.
As a specialist with experience
in this field, I am convinced that we
will be able to manage a large scale
outbreak within the poultry industry.
There is one condition: the industry
has to take this very seriously and
needs to take the responsibility and
act—starting yesterday.
Harm Kiezebrink is an independent
consultant who works for the poultry
industry, governments, and veterinary
services worldwide. In addition to the crises
in Holland and Belgium, Harm was involved
in control outbreak planning in other
European countries such as Spain, Portugal,
France, England and Germany, as well as in
Asia (China, Thailand and Vietnam). Harm
is currently active in Romania advising the
minister of agriculture and representatives of
the Romanian poultry industry.
• Carbon monoxide. Don’t use
carbon monoxide. In addition
to availability problems,
carbon monoxide is highly
flammable, and caused a fire
on at least one farm during
the Dutch outbreak.
In practice, a variety of different
methods must be in place before an
outbreak occurs.
Lesson Seven: Beware of
Unexpected Limitations
Whatever method is chosen,
success in culling always comes
down to the entire operation, rather
than the technique. The make or
break factor in Holland was disposal
of the dead birds. In Holland, the
method of choice was rendering
the animals. The rendering capacity
dictated the speed of operation. The
“It is important to go
back to common sense
and stay with the facts.
There is no reason to
panic yet.”
9. 9
Depopulation of Poultry Flocks during Disease Outbreaks
and Other Catastrophic Events
by Dr. Nathaniel L. Tablante
Depopulation of poultry flocks is
necessary during infectious disease
outbreaks and natural disasters. In
the case of avian influenza, which
has gained notoriety in recent years
because of the potential risk to
human health, destruction of infect-
ed flocks is required in order to
prevent further spread of the disease.
The destruction of these flocks must
be done as quickly as possible, using
proper and humane methods of mass
euthanasia.
The word euthanasia is derived
from two Greek words that mean
“good death.” The term essentially
refers to a humane death that occurs
with a minimum of fear, pain, and
distress. In 2000, the American
Veterinary Medical Association
(AVMA) developed specific
guidelines on the euthanasia of
animals. The 2000 Report of the
AVMA Panel on Euthanasia states
that “under unusual conditions
like disease outbreaks and natural
disasters that require depopulation,
the most appropriate technique that
minimizes human and animal health
concerns must be used.” According
to these guidelines, the method
of euthanasia must result in rapid
loss of consciousness, cardiac or
respiratory arrest, and ultimate loss
of brain function.
Choosing the method of
euthanasia depends on several
factors such as human safety, skill
of the operator, aesthetics, cost,
other limitations, and consideration
of the humaneness of the method.
Currently, only two methods of mass
euthanasia of poultry are considered
acceptable by the AVMA. These are
1) cervical dislocation, and 2) use
of inhalant gases such as carbon
dioxide (CO2). In a disease outbreak
where prompt response is critical,
cervical dislocation is impractical,
labor intensive, and time consuming
as it involves individual handling
of thousands of birds. Therefore,
inhalant gases like CO2 are widely
used to euthanize large numbers of
birds at a time. Carbon dioxide for
mass euthanasia of poultry, although
not perfect, is widely used because
it is inexpensive, readily available,
and poses minimal risk to humans.
To be effective, a concentration of
60 to 70 percent must be achieved.
Broiler chickens and turkeys are
sensitive to CO2 but waterfowl are
more resistant and require higher
concentrations and longer exposure
time.
For meat-type poultry, the
following methods of CO2
euthanasia have been developed and
used in actual AI outbreaks:
1. Whole house method.
• Used mainly in breeder
houses.
• Involves the use of a CO2
tanker truck.
2. Partial house method.
• Used also in breeder
houses.
• Involves driving birds into
one end of the house in
the litter area and sealing
the area off with a sheet of
poly.
• Utilizes CO2 tanker trucks
or 50 lb. cylinders.
3. Portable panels with tarp.
• Works best with turkeys.
• Involves the use of ply-
wood panels that are set up
against posts.
• Birds are driven into the
enclosure formed by the
panels.
• CO2 cylinders are placed
on the floor and a sheet of
poly is placed on top of the
birds using the top edge of
the panels for support.
4. Livehaul euthanasia cabinet.
• Ideal for broilers.
• Utilizes regular livehaul
crates.
• Fabricated steel cabinet is
placed on top of crate con-
10. 10
taining the birds.
• CO2 is pumped into the
cabinet.
5. Poly euthanasia tent.
• Ideal for broilers in clear
span houses.
• Birds are driven to one end
of the house one group at a
time.
• CO2 cylinders are placed
on the floor and poly is
placed on top of birds in
two opposite and overlap-
ping layers.
• Works well with in-house
composting of carcasses.
These methods were developed
and later refined by poultry industry
personnel during actual outbreaks of
avian influenza. Those involved in
depopulation of poultry flocks know
fully well that mass euthanasia of
poultry is not a pleasant task. It is
physically and emotionally stressful
for all personnel involved in the
process and distressful for poultry
as well if the euthanasia is done
improperly. However, in the event of
a catastrophic disease such as avian
influenza, it is a necessary evil. In
order to expedite the process, protect
the welfare of poultry, and ease the
physical and emotional burden on
humans, the following criteria must
be met:
1. All personnel involved in
depopulation of poultry
flocks must undergo intensive
training on emergency
preparedness, poultry welfare,
and methods of euthanasia,
and must follow the Centers
for Disease Control guidelines
for poultry workers involved
in avian influenza control.
(See http://www.cdc.gov/flu/
avian/professional/protect-
guid.htm for details.)
2. The poultry industry, along
with state and federal agency
representatives must prepare
in advance for an emergency
poultry disease outbreak
by having an action plan in
place, including provisions for
necessary personnel, supplies,
and equipment.
3. The different methods of
CO2 euthanasia must only be
performed under the direct
supervision of a veterinarian
or trained professional. This
professional must insure
that the birds are treated in
a humane manner from start
to finish. Acts of animal
cruelty like the use of baseball
bats and woodchippers are
absolutely forbidden and
those who commit such
inhumane acts will be
prosecuted accordingly.
4. A safety officer to monitor
compliance with OSHA
guidelines and ensure safe
levels of CO2 for humans
must always be present during
the euthanasia procedure.
Practicing the different methods
of mass euthanasia and carcass
disposal through simulated exercises
is strongly recommended. Not
having the necessary skills and
resources when an outbreak occurs
can result in the loss of valuable
time to control the outbreak, which
may result in a major economic
disaster and bad publicity. Extension
specialists and poultry professionals
must play a key role in educating
poultry workers, farmers, and all
those involved in disease control
and eradication efforts on proper
methods of euthanasia and carcass
disposal.
References:
American Veterinary Medical Association, 2000
Report of the AVMA Panel on Euthanasia, J
Am Vet Med Assoc 2001, 218:669-696.
UC Davis, Center for Animal Welfare, Euthanasia
of Poultry: Considerations for Producers,
Transporters, and Veterinarians (undated).
Disposal Options for Avian Influenza Flocks
by Bud Malone
Are you prepared to deal with
catastrophic mortality disposal due
to Avian Influenza (AI) on your
farms? Do you have disposal pro-
cedures, materials, knowledge and
approvals in hand that allow you to
respond to this kind of event in a
swift, biosecure, economical, envi-
ronmentally and socially acceptable
manner? There have been several
recent examples in which there was
uncertainty and lack of knowledge
on methods of mass disposal, lack
of preparation to deal with this type
of catastrophic event, and perhaps
more important, not having proce-
dures pre-approved by local and
state regulatory authorities. The
consequence of these situations has
been conflict, delays in responding
to the emergency at the most critical
time period, and added overall cost
to deal with the disease crisis.
The following are some of the
questions that need to be asked
when analyzing potential disposal
options for a disease outbreak.
What local, state, and/or federal
regulations apply to this situation?
What are the viable disposal options
given the situation on each farm and
house on that farm? Is the house
clear-span or pole? How many and
what size of birds are involved?
What resources, equipment and
disposal options are available on the
farm, from the poultry company or
agency(s) overseeing this matter?
Is the AI a low or high pathogenic
11. 11
form? With the recent media and
human health attention given to
“bird flu” (H5N1) in Asia and now
Europe, additional safeguards are
needed to insure public health. And
let’s not forget, how will the public
perceive the disposal option being
recommended?
The following are some brief
highlights of disposal options for
AI infected flocks used in the U.S.
Local, state and federal guidelines
will dictate which options are
appropriate given the nature of the
AI event.
Burial. At one time, on-farm
burial was the predominant
disposal option for many types of
catastrophic losses. This practice is
one of the simplest and most cost-
effective ways to deal with mass
mortality losses. Trenches with
carcasses placed 2-3 feet above the
seasonal high water table, placed
at a maximum of 4 feet thick and
covered with 2 feet of fill on top
of the birds has been used for
various types of mass mortality
losses. Although some states have
previously relaxed environmental
standards for burial when dealing
with an emergency, this situation is
changing due to increasing water
quality and public perception
concerns. In many Delmarva
locations having high seasonal water
tables, finding a suitable location
can be a major challenge. In a
disease emergency, trench burial
above the water table may be needed
but not the preferred method of
disposal of AI-infected flocks.
Sanitary Landfill. The use of
sanitary landfills has been used
for mass disposal of AI flocks
in the last few decades. Since all
landfills do not accept carcasses,
pre-approval is required and there
can be logistical challenges when
coordinating the transportation
and deposition of large volumes
of carcasses to these sites. Costs
associated with transportation and
tipping fees can be significant.
During several recent AI outbreaks,
there were indications that disposal
options that removed infected
carcasses from farms posed a
potential risk of spreading the virus
to other farms.
Incineration. Portable
incineration units (i.e., Air
Curtain™) have been used on a
limited scale in recent AI outbreaks.
Although the end product is
very biosecure, there are some
logistical and environmental
issues with this procedure. The
units need to be transported to
the region of the country having
the catastrophic losses. Carcasses
are then transported to a central
and preferably remote receiving
site. The incineration process is
somewhat slow, loading decomposed
carcasses poses a problem and it
will require disposal of 0.3 tons of
ash per ton of carcass. Without the
proper fuel source and supervision
of the process, smoke and odor
can create nuisance complaints.
Based on Virginia’s experience
with incineration during their 2002
outbreak, this disposal option will
likely be a low priority for any
future AI events.
Composting. There has
been increasing acceptance
of composting as a practical,
economical and environmentally
sound method for disposal of many
types of catastrophic mortality
events. Following a major heat
loss on the Delmarva Peninsula
in 1995, the local universities
conducted a demonstration and
developed guidelines (Carr et
al., 1996) for outside windrow
composting of catastrophic heat-
loss mortality events. In 2003
another demonstration was
conducted on Delmarva to evaluate
and demonstrate the windrow
composting procedure inside poultry
houses. A year later on Delmarva,
this procedure was implemented as
a means to contain and inactivate
the H7N2 AI virus in the carcasses
and litter on the three infected farms
(Malone et al., 2004). The procedure
used on these farms involved the
formation of a single windrow 10
to 12 feet wide by 3 to 5 feet high
down the center of the house. The
litter and carcasses were mixed
uniformly and capped with litter or
sawdust to cover exposed carcasses.
This procedure requires 0.8 inches
of litter/carbon per pound of carcass
per square foot floor space (Tablante
and Malone, 2005). Crushing
or shredding carcasses prior to
windrowing reduces the additional
carbon requirement to compost
large carcasses such as roasters and
turkeys (Bendfeldt et al., 2005).
12. After ~2 weeks the windrows can be
turned in the house, capped to cover
any exposed tissue, and allowed to
compost for another 10 days prior
to removal. An alternative procedure
is to remove the compost after
the first 2 weeks and place it in a
covered windrow outside the house.
Temperatures in the compost exceed
130º F, enough to inactive the virus
within a short period of time.
An Ag-Bag composting system
has been employed on a limited
scale during several recent AI events
in the U.S. and Canada. This system
requires specialized equipment
to mix carcasses with the carbon
source, load the mixture into the
bags and maintain proper aeration.
Due to logistical considerations,
it may be more appropriate to
transport the carcasses to a central
site for composting with this system.
Since broiler breeder and caged
layer farms may have limited on-
farm carbon sources and these
types of carcasses tend to be more
difficult to compost, transporting
these mortalities to a centralized and
professionally operated Ag-Bag site
may be appropriate.
In summary, when the decision
is made to depopulate a farm for
disease control purposes, selection
of the disposal method should focus
on minimizing disease spread.
Several recent AI events suggest
every effort should be made to
inactivate AI virus prior to carcass
(and litter) removal from the house.
There is growing consensus that
in-house composting is the most
biosecure disposal method for
a flock with a highly infectious
disease like avian influenza.
References
Bendfeldt, E., R. Peer, G. Flory, G. Evanylo, L.
Carr and G. Malone. 2005. Can Catastrophic
Turkey Mortalities be Composted In-House
as a Means of Disposal? Symposium on
Composting Mortalities and Slaughterhouse
Residuals. Portland, MA.
Carr, L., H. Brodie, J. Martin, Jr., G. Malone,
D. Palmer and N. Zimmermann. 1996.
“Composting Catastrophic Event Poultry
Mortalities.” University of Maryland Fact
Sheet No. 732.
Malone, G., S. Cloud, R. Alphin, L. Carr and N.
Tablante. 2004. Delmarva in-house carcass
composting experiences. Proceedings 39th
National Meeting on Poultry Health and
Processing. Ocean City, MD. pp. 27-29.
Tablante, N. and G. Malone. 2005. Guidelines for
In-House Composting of Poultry Mortalities
Due to Catastrophic Disease. Compact disk
available from Universities of Maryland and
Delaware.
MARYLAND COOPERATIVE EXTENSION
U.S. Department of Agriculture
University of Maryland, College Park
College Park, Maryland 20742
Issued in furtherance of Cooperative Extension work, acts of May 8 and June 30, 1914, in cooperation with the U.S. Department of Agriculture, University of Maryland, College Park, and local governments.
Cheng-i Wei, Director of Maryland Cooperative Extension, University of Maryland.
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