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From: TSS ()
C H A P T E R 2 . 3 . 1 3 . BOVINE SPONGIFORM ENCEPHALOPATHY Article 2.3.13.1. The recommendations in this Chapter are intended to manage the human and animal health risks associated with the presence of the bovine spongiform encephalopathy (BSE) agent in cattle (Bos taurus and B. indicus) only. 1) When authorising import or transit of the following commodities and any products made from these commodities and containing no other tissues from cattle, Veterinary Administrations should not require any BSE related conditions, regardless of the BSE risk status of the cattle population of the exporting country, zone or compartment: a) milk and milk products; b) semen and in vivo derived cattle embryos collected and handled in accordance with the recommendations of the International Embryo Transfer Society; c) hides and skins; d) gelatin and collagen prepared exclusively from hides and skins; e) protein-free tallow (maximum level of insoluble impurities of 0.15% in weight) and derivatives made from this tallow; f) dicalcium phosphate (with no trace of protein or fat); g) deboned skeletal muscle meat (excluding mechanically separated meat) from cattle 30 months of age or less, which were not subjected to a stunning process, prior to slaughter, with a device injecting compressed air or gas into the cranial cavity, or to a pithing process, and which were subject to ante- and post-mortem inspection and were not suspect or confirmed BSE cases; and which has been prepared in a manner to avoid contamination with tissues listed in Article 2.3.13.13.; h) blood and blood by-products, from cattle which were not subjected to a stunning process, prior to slaughter, with a device injecting compressed air or gas into the cranial cavity, or to a pithing process. 2) When authorising import or transit of other commodities listed in this chapter, Veterinary Administrations should require the conditions prescribed in this Chapter relevant to the BSE risk status of the cattle population of the exporting country, zone or compartment. Standards for diagnostic tests are described in the Terrestrial Manual. Article 2.3.13.2. The BSE risk status of the cattle population of a country, zone or compartment should be determined on the basis of the following criteria: 1) the outcome of a risk assessment (which is reviewed annually), based on Section 1.3., identifying all potential factors for BSE occurrence and their historic perspective: 2005 OIE Terrestrial Animal Health Code 2 a) Release assessment Release assessment consists of assessing the likelihood that a transmissible spongiform encephalopathy (TSE) agent has been introduced into the cattle population from a pre-existing TSE in the indigenous ruminant population or via commodities potentially contaminated with a TSE agent, through a consideration of the following: i) the presence or absence of animal TSE agents in the country or zone or compartment and, if present, their prevalence based on the outcomes of surveillance; ii) meat-and-bone meal or greaves from the indigenous ruminant population; iii) imported meat-and-bone meal or greaves; iv) imported live animals; v) imported animal feed and feed ingredients; vi) imported products of ruminant origin for human consumption, which may have contained tissues listed in Article 2.3.13.13. and may have been fed to cattle; vii) imported products of ruminant origin for in vivo use in cattle. Surveillance and other epidemiological investigations (especially surveillance for BSE conducted on the cattle population) relevant to the above should be taken into account in carrying out the assessment. b) Exposure assessment If the release assessment identifies a risk factor, an exposure assessment should be conducted, consisting of assessing the likelihood of exposure of the BSE agent to cattle, through a consideration of the following: i) recycling and amplification of the BSE agent through consumption by cattle of meat-andbone meal or greaves of ruminant origin, or other feed or feed ingredients contaminated with these; ii) the use of ruminant carcasses (including from fallen stock), by-products and slaughterhouse waste, the parameters of the rendering processes and the methods of animal feed manufacture; iii) the feeding or not of ruminants with meat-and-bone meal and greaves derived from ruminants, including measures to prevent cross-contamination of animal feed; iv) the level of surveillance for BSE conducted on the cattle population to that time and the results of that surveillance. 2) on-going awareness programme for veterinarians, farmers, and workers involved in transportation, marketing and slaughter of cattle to encourage reporting of all cases showing clinical signs consistent with BSE in target sub-populations as defined in Appendix 3.8.4.; 2005 OIE Terrestrial Animal Health Code 3 3) the compulsory notification and investigation of all cattle showing clinical signs consistent with BSE; 4) the examination in an approved laboratory of brain or other tissues collected within the framework of the aforementioned surveillance and monitoring system. When the risk assessment (which takes into account the surveillance referred to in the release and exposure assessments above) demonstrates non-negligible risk, the country should conduct Type A surveillance in accordance with Appendix 3.8.4. When the risk assessment (which takes into account the surveillance referred to in the release and exposure assessments above) demonstrates negligible risk, the country should conduct Type B surveillance in accordance with Appendix 3.8.4. Article 2.3.13.3. Negligible BSE risk Commodities from the cattle population of a country, zone or compartment pose a negligible risk of transmitting the BSE agent should the following conditions be met: 1) a risk assessment, as described in point 1) of Article 2.3.13.2., has been conducted in order to identify the historical and existing risk factors and the country has been demonstrated that appropriate generic measures have been taken for the relevant period of time defined below to manage all risk identified; 2) the country has demonstrated that Type B surveillance in accordance with Appendix 3.8.4. is in place, 3) EITHER: a) there has been no case of BSE, or any case of BSE has been demonstrated to have been imported and has been completely destroyed, and: i) the criteria in points 2) to 4) of Article 2.3.13.2. have been complied with for at least 7 years; and ii) it has been demonstrated, through an appropriate level of control and audit, that for at least 8 years meat-and-bone meal or greaves derived from ruminants has not been fed to ruminants; OR b) the last indigenous case of BSE was reported more than 7 years ago; and i) the criteria in points 2) to 4) of Article 2.3.13.2. have been complied with for at least 7 years; and ii) it has been demonstrated, thorough an appropriate level of control and audit, that for at least 8 years meat-and-bone meal and greaves derived from ruminants has not been fed to ruminants; and iii) all BSE cases, as well as: - all the progeny of female cases, born within 2 years prior to or after clinical onset of the disease, and 2005 OIE Terrestrial Animal Health Code 4 - all cattle which, during their first year of life, were reared with the BSE cases during their first year of life, and which investigation showed consumed the same potentially contaminated feed during that period, or - if the results of the investigation are inconclusive, all cattle born in the same herd as, and within 12 months of the birth of, the BSE cases, if alive in the country, zone or compartment, are permanently identified, and their movements controlled, and when slaughtered or at death, are completely destroyed. Article 2.3.13.4. Controlled BSE risk Commodities from the cattle population of a country, zone or compartment pose a controlled risk of transmitting the BSE agent, should the following conditions be met: 1) a risk assessment, as described in point 1) of Article 2.3.13.2., has been conducted in order to identify the historical and existing risk factors, and the country has not demonstrated that appropriate generic measures have been taken for the relevant period of time defined below to manage all risks identified; 2) the country has demonstrated that Type A surveillance in accordance with Appendix 3.8.4. is in place; 3) EITHER a) there has been no case of BSE or any case of BSE has been demonstrated to have been imported and has been completely destroyed, the criteria in points 2) to 4) of Article 2.3.13.2. are complied with, and it can be demonstrated, through an appropriate level of control and audit, that meat-and-bone meal and greaves derived from ruminants has not been fed to ruminants, but at least one of the following two conditions applies: i) the criteria in points 2) to 4) of Article 2.3.13.2. have not been complied with for 7 years; ii) it cannot be demonstrated that controls over the feeding of meat-and-bone meal or greaves derived from ruminants to ruminants have been in place for 8 years; OR b) there has been an indigenous case of BSE reported, the criteria in points 2) to 4) of Article 2.3.13.2. are complied with, and it can be demonstrated, through an appropriate level of control and audit that meat-and-bone meal and greaves derived from ruminants have not been fed to ruminants, but at least one of the following two conditions applies: i) the criteria in points 2) to 4) of Article 2.3.13.2. have not been complied with for 7 years; ii) it cannot be demonstrated that controls over the feeding of meat-and-bone meal and greaves derived from ruminants to ruminants have been in place for 8 years; AND iii) all BSE cases, as well as: - all the progeny of female cases, born within 2 years prior to or after clinical onset of the disease, and 2005 OIE Terrestrial Animal Health Code 5 - all cattle which, during their first year of life, were reared with the BSE cases during their first year of life, and which investigation showed consumed the same potentially contaminated feed during that period, or - if the results of the investigation are inconclusive, all cattle born in the same herd as, and within 12 months of the birth of, the BSE cases, if alive in the country, zone or compartment, are permanently identified, and their movements controlled, and when slaughtered or at death, are completely destroyed. Article 2.3.13.5. Undetermined BSE risk The cattle population of a country, zone or compartment poses an undetermined BSE risk if it cannot be demonstrated that it meets the requirements of another category. Article 2.3.13.6. When importing from a country, zone or compartment posing a negligible BSE risk, Veterinary Administrations should require: for all commodities from cattle not listed in point 1) of Article 2.3.13.1. the presentation of an international veterinary certificate attesting that the country or zone/compartment complies with the conditions in Article 2.3.13.3. Article 2.3.13.7. When importing from a country, zone or compartment posing a controlled BSE risk, Veterinary Administrations should require: for cattle the presentation of an international veterinary certificate attesting that: 1) the country, zone or compartment complies with the conditions in Article 2.3.13.4.; 2) cattle selected for export are identified by a permanent identification system enabling them to be traced back to the dam and herd of origin, and are not exposed cattle as described in point 2) c) iii) of Article 2.3.13.4.; 3) in the case of a country, zone or compartment with an indigenous case, cattle selected for export were born after the date from which the ban on the feeding of ruminants with meat-and-bone meal and greaves derived from ruminants had been effectively enforced. Article 2.3.13.8. When importing from a country, zone or compartment with an undetermined BSE risk, Veterinary Administrations should require: for cattle the presentation of an international veterinary certificate attesting that: 1) the feeding of ruminants with meat-and-bone meal and greaves derived from ruminants has been banned and the ban has been effectively enforced; 2005 OIE Terrestrial Animal Health Code 6 2) all BSE cases, as well as: a) all the progeny of female cases, born within 2 years prior to or after clinical onset of the disease, and b) all cattle which, during their first year of life, were reared with the BSE cases during their first year of life, and, which investigation showed consumed the same potentially contaminated feed during that period, or c) if the results of the investigation are inconclusive, all cattle born in the same herd as, and within 12 months of the birth of, the BSE cases, if alive in the country, zone or compartment, are permanently identified, and their movements controlled, and when slaughtered or at death, are completely destroyed; 3) cattle selected for export: a) are identified by a permanent identification system enabling them to be traced back to the dam and herd of origin and are not the progeny of BSE suspect or confirmed females; b) were born at least 2 years after the date from which the ban on the feeding of ruminants with meat-and-bone meal and greaves derived from ruminants was effectively enforced. Article 2.3.13.9. When importing from a country, zone or compartment posing a negligible BSE risk, Veterinary Administrations should require: for fresh meat and meat products from cattle (other than that listed in point 1) of Article 2.3.13.1.) the presentation of an international veterinary certificate attesting that: 1) the country, zone or compartment complies with the conditions in Article 2.3.13.3.; 2) ante-mortem and post-mortem inspections were carried out on all cattle from which the fresh meat or meat products originate. Article 2.3.13.10. When importing from a country, zone or compartment posing a controlled BSE risk, Veterinary Administrations should require: for fresh meat and meat products from cattle (other than those listed in point 1) of Article 2.3.13.1.) the presentation of an international veterinary certificate attesting that: 1) the country, zone or compartment complies with the conditions in Article 2.3.13.4.; 2) ante-mortem and post-mortem inspections were carried out on all cattle from which the fresh meat and meat products originate; 3) cattle from which the fresh meat and meat products destined for export originate were not subjected to a stunning process, prior to slaughter, with a device injecting compressed air or gas into the cranial cavity, or to a pithing process; 4) the fresh meat and meat products do not contain: a) the tissues listed in Article 2.3.13.13., b) mechanically separated meat from the skull and vertebral column from cattle over 30 months of age, all of which have been completely removed in a manner to avoid contamination of the fresh meat and meat products. 2005 OIE Terrestrial Animal Health Code 7 Article 2.3.13.11. When importing from a country, zone or compartment with an undetermined BSE risk, Veterinary Administrations should require: for fresh meat and meat products from cattle (other than those listed in point 1) of Article 2.3.13.1.) the presentation of an international veterinary certificate attesting that: 1) the cattle from which the fresh meat and meat products originate: a) are not suspect or confirmed BSE cases; b) have not been fed meat-and-bone meal or greaves; c) were subjected to ante-mortem and post-mortem inspections; d) were not subjected to a stunning process, prior to slaughter, with a device injecting compressed air or gas into the cranial cavity, or to a pithing process; 2) the fresh meat and meat products do not contain: a) the tissues listed in Article 2.3.13.13., b) nervous and lymphatic tissues exposed during the deboning process, c) mechanically separated meat from the skull and vertebral column from cattle over 12 months of age, all of which have been completely removed in a manner to avoid contamination of the fresh meat and meat products. Article 2.3.13.12. Ruminant-derived meat-and-bone meal or greaves, or any commodities containing such products, which originate from a country, zone or compartment defined in Articles 2.3.13.4. and 2.3.13.5. should not be traded between countries. Article 2.3.13.13. 1) From cattle of any age originating from a country, zone or compartment defined in Articles 2.3.13.4. and 2.3.13.5., the following commodities, and any commodity contaminated by them, should not be traded for the preparation of food, feed, fertilisers, cosmetics, pharmaceuticals including biologicals, or medical devices: tonsils and distal ileum, and protein products derived thereof. Food, feed, fertilisers, cosmetics, pharmaceuticals or medical devices prepared using these commodities should also not be traded. 2) From cattle that were at the time of slaughter over 30 months of age originating from a country, zone or compartment defined in Article 2.3.13.4., the following commodities, and any commodity contaminated by them, should not be traded for the preparation of food, feed, fertilisers, cosmetics, pharmaceuticals including biologicals, or medical devices: brains, eyes, spinal cord, skull, vertebral column and derived protein products. Food, feed, fertilisers, cosmetics, pharmaceuticals or medical devices prepared using these commodities should also not be traded. 3) From cattle that were at the time of slaughter over 12 months of age originating from a country, zone or compartment defined in Article 2.3.13.5., the following commodities, and any commodity contaminated by them, should not be traded for the preparation of food, feed, fertilisers, cosmetics, pharmaceuticals including biologicals, or medical devices: brains, eyes, spinal cord, skull, vertebral column and derived protein products. Food, feed, fertilisers, cosmetics, pharmaceuticals or medical devices prepared using these commodities should also not be traded. 2005 OIE Terrestrial Animal Health Code 8 Article 2.3.13.14. Veterinary Administrations of importing countries should require: for gelatin and collagen prepared from bones and intended for food or feed, cosmetics, pharmaceuticals including biologicals, or medical devices the presentation of an international veterinary certificate attesting that the commodities came from: 1) a country, zone or compartment posing a negligible BSE risk; or 2) a country, zone or compartment posing a controlled BSE risk; and a) skulls and vertebrae (except tail vertebrae) have been excluded; b) the bones have been subjected to a process which includes all the following steps: i) pressure washing (degreasing), ii) acid demineralisation, iii) prolonged alkaline treatment, iv) filtration, v) sterilisation at =138°C for a minimum of 4 seconds, or to an equivalent process in terms of infectivity reduction. Article 2.3.13.15. Veterinary Administrations of importing countries should require: for tallow and dicalcium phosphate (other than protein-free tallow as defined in Article 2.3.13.1.) intended for food, feed, fertilisers, cosmetics, pharmaceuticals including biologicals, or medical devices the presentation of an international veterinary certificate attesting that it originates from: 1) a country, zone or compartment posing a negligible BSE risk; or 2) a country, zone or compartment posing a controlled BSE risk, and it originates from cattle which have been subjected to ante-mortem and post-mortem inspection and has not been prepared using the tissues listed in point 2 of Article 2.3.13.13. Article 2.3.13.16. Veterinary Administrations of importing countries should require: for tallow derivatives (other than those made from protein-free tallow as defined in Article 2.3.13.1.) intended for food, feed, fertilisers, cosmetics, pharmaceuticals including biologicals, or medical devices the presentation of an international veterinary certificate attesting that: 1) they originate from a country, zone or compartment posing a negligible BSE risk measures; or 2) they have been produced by hydrolysis, saponification or transesterification using high temperature and pressure. 2005 OIE Terrestrial Animal Health Code 9 APPENDI X 3 . 8 . 4 . SURVEILLANCE FOR BOVINE SPONGIFORM ENCEPHALOPATHY Article 3.8.4.1. Introduction 1) Depending on the bovine spongiform encephalopathy (BSE) risk category of a country, zone or compartment, surveillance for BSE may have one or more goals: a) detecting BSE, to a pre-determined design prevalence, in a country, zone or compartment; b) monitoring the evolution of BSE in a country, zone or compartment; c) monitoring the effectiveness of a feed ban and/or other risk mitigation measures, in conjunction with auditing, etc; d) supporting a claimed BSE status; e) gaining or regaining a higher BSE status. 2) When the BSE agent is present in a country or zone, the cattle population will comprise the following sectors, in order of decreasing size: a) cattle not exposed to the infective agent; b) cattle exposed but not infected; c) infected cattle, which may lie within one of three stages in the progress of BSE: i) the majority will die or be killed before reaching a stage at which BSE is detectable by current methods; ii) some will progress to a stage at which BSE is detectable by testing before clinical signs appear; iii) the smallest number will show clinical signs. 3) The BSE status of a country, zone or compartment cannot be determined only on the basis of a surveillance programme but should be determined in accordance with all the factors listed in Article 2.3.13.2. The surveillance programme should take into account the diagnostic limitations associated with the above sectors and the relative distributions of infected cattle among them. 4) With respect to the distribution and expression of the BSE agent within the sectors described above, the following four subpopulations of cattle have been identified for surveillance purposes: a) cattle over 30 months of age displaying behavioural or clinical signs consistent with BSE; b) cattle over 30 months of age that are non-ambulatory, recumbent, unable to rise or to walk without assistance; cattle over 30 months of age sent for emergency slaughter or condemned at ante-mortem inspection (casualty, emergency slaughter or downer cattle); 2005 OIE Terrestrial Animal Health Code 10 c) cattle over 30 months of age which are found dead on farm, during transport or at an abattoir (fallen stock). d) cattle over 36 months of age at routine slaughter. 5) A gradient is used to describe the relative value of surveillance applied to each subpopulation. Surveillance should focus on the first subpopulation, but investigation of other subpopulations will help to provide an accurate assessment of the BSE situation in the country, zone or compartment. All countries should sample at least three of the four subpopulations. This approach is consistent with Appendix 3.8.1. on surveillance and monitoring of animal health. Article 3.8.4.2. Description of cattle subpopulations 1) Cattle over 30 months of age displaying behavioural or clinical signs consistent with BSE Cattle affected by illnesses that are refractory to treatment, and displaying progressive behavioural changes such as excitability, persistent kicking when milked, changes in herd hierarchical status, hesitation at doors, gates and barriers, as well as those displaying progressive neurological signs without signs of infectious illness are candidates for examination. These behavioural changes, being very subtle, are best identified by those who handle animals on a daily basis. Since BSE causes no pathognomonic clinical signs, all countries with cattle populations will observe individual animals displaying clinical signs consistent with BSE. It should be recognised that cases may display only some of these signs, which may also vary in severity, and such animals should still be investigated as potential BSE affected animals. The rate at which such suspicious cases are likely to occur will differ among epidemiological situations and cannot therefore be predicted reliably. This subpopulation, particularly cattle over 30 months of age, is the one exhibiting the highest prevalence. The recognition greatly depends on the owner’s awareness and observation of suspect animals. The reporting of these suspect animals when at the farm will depend on the owner’s motivation based on cost and socio-economic repercussions. 2) Cattle over 30 months of age that are non-ambulatory, recumbent, unable to rise or to walk without assistance; cattle over 30 months of age sent for emergency slaughter or condemned at ante-mortem inspection (casualty or emergency slaughter, or downer cattle) These cattle may have exhibited some of the clinical signs listed above which were not recognised as being consistent with BSE. Experience in countries where BSE has been identified indicates that this subpopulation is the one demonstrating the second highest prevalence. For that reason, it is the second most appropriate population to target in order to detect BSE. 3) Cattle over 30 months of age which are found dead on farm, during transport or at an abattoir (fallen stock) These cattle may have exhibited some of the clinical signs listed above prior to death, but were not recognised as being consistent with BSE. Experience in countries where BSE has been identified indicates that this subpopulation is the one demonstrating the third highest prevalence. 4) Cattle over 36 months of age at routine slaughter Experience in countries where BSE has been identified indicates that this subpopulation is the one demonstrating the lowest prevalence. For that reason, it is the least appropriate population to target in order to detect BSE. However, sampling in this subpopulation may be an aide in monitoring the progress of the epizootic and the efficacy of control measures applied, because it offers continuous access to a cattle population of known class, age structure and geographical origin. Testing of routine slaughter cattle younger than 36 months is of relatively very little value (Table 2). 2005 OIE Terrestrial Animal Health Code 11 Within each of the above subpopulations, countries may wish to target cattle identifiable as imported from countries or zones not free from BSE, cattle which have consumed potentially contaminated feedstuffs from countries or zones not free from BSE, offspring of BSE affected cows and cattle which have consumed feedstuffs potentially contaminated with other TSE agents. When establishing a surveillance strategy, authorities must take into account inherent difficulties of obtaining samples on farm. These difficulties include higher cost, necessity for education and motivation of owners, counteracting potentially negative socio-economic implication. Authorities must find ways to overcome these difficulties. Article 3.8.4.3. 1) Implementation of type A surveillance In order to implement efficiently a surveillance strategy for BSE, a country must use good quality data (or reliable estimates) concerning the age distribution of its adult cattle population and the number of cattle tested for BSE stratified by age and by subpopulation. The application of the following procedure will allow the detection of BSE prevalence of at least one case per 100,000 in the adult cattle population, at a confidence level of 95% in the country, zone or compartment of concern. This Appendix utilises Tables 1 and 2 to determine a desired surveillance point target and the point values of surveillance samples collected. The approach assigns ‘point values’ to each sample, based on the subpopulation from which it was collected and the likelihood of detecting infected cattle in that subpopulation. The number of points a sample is assigned is determined by the subpopulation from which the sample is collected and the age of the animal sampled. The total points accumulation is then periodically compared to the target number of points for a country, zone or compartment. A country should design its surveillance strategy to ensure that samples are representative of the herd of the country, zone or compartment, and include consideration of demographic factors such as production type and geographic location, and the potential influence of culturally unique husbandry practices. The approach used and the assumptions made should be fully documented, and the documentation retained for 7 years. The points targets and surveillance point values in the appendix were obtained by applying the following factors to a statistical model: a) a prevalence of either at least one case per million or one case per 100,000 of the adult cattle population; b) a confidence level of 95%; c) the pathogenesis, and pathological and clinical expression of BSE: i) sensitivity of diagnostic methods used; ii) relative frequency of expression by age; iii) relative frequency of expression within each subpopulation; iv) interval between clinical pathological change and clinical expression; d) demographics of the cattle population, including age distribution; e) influence of BSE on culling or attrition of animals from the cattle population via the four subpopulations; f) percentage of infected animals in the cattle population which are not detected. 2005 OIE Terrestrial Animal Health Code 12 Although the procedure accepts very basic information about a cattle population, and can be used with estimates and less precise data, careful collection and documentation of the data significantly enhance their value. Since samples from clinical suspect animals provide many times more information than samples from healthy or dead-of-unknown-cause animals, careful attention to the input data can substantially decrease the procedure’s cost and the number of samples needed. The essential input data are: g) cattle population numbers stratified by age; h) the number of cattle tested for BSE stratified by age and by subpopulation. 2) Maintenance (type B) surveillance For countries which have demonstrated through risk assessment (including surveillance) that they meet the requirements for ‘negligible risk without commodity-specific risk mitigation measures’, surveillance should continue at a reduced, maintenance level. In order to implement efficiently a maintenance surveillance strategy for BSE, a country must use good quality data (or reliable estimates) concerning the age distribution of its adult cattle population and the number of cattle tested for BSE stratified by age and by subpopulation. The application of the following procedure will allow the detection of BSE prevalence of at least one case per 50,000 in the adult cattle population, at a confidence level of 95% in the country, zone or compartment of concern. This Appendix utilises Tables 1 and 2 to determine a desired surveillance point target and the point values of surveillance samples collected. Maintenance surveillance should focus on the higher prevalence subpopulations (especially clinical suspects). The number of clinical suspect samples taken annually should approximate the number of samples taken annually from clinical suspect cases during the time taken to reach the country, zone or compartment’s BSE status (to a maximum of seven years). Article 3.8.4.4. 1) Selecting the points target The desired surveillance points target is selected from Table 1, which shows target points for adult cattle populations of different sizes. A country’s adult cattle population size may be estimated or may be set at one million because, for statistical reasons, one million is the point beyond which sample size does not further increase with population size. The target depends on the design prevalence chosen by the country. 2005 OIE Terrestrial Animal Health Code 13 Table 1 Points targets for different adult cattle population sizes in a country, zone or compartment which has not identified any BSE cases Target points for country, zone or compartment with 0 cases, 95% confidence Adult Cattle Population Size (24 months and older) *DP 1/100,000 *DP 1/50,000 = 1,000,000 300,000 150,000 800,000 – 1,000,000 240,000 120,000 600,000 – 800,000 180,000 90,000 400,000 – 600,000 120,000 60,000 200,000 – 400,000 60,000 30,000 100,000 – 200,000 30,000 15,000 50,000 – 100,000 15,000 7,500 *DP is the maximum possible prevalence or "design prevalence". 2) Determining the point values of samples collected Table 2 can be used to determine the point values of the surveillance samples collected. The approach assigns point values to each sample according to the likelihood of detecting infection based on the subpopulation from which the sample was collected and the age of the animal sampled. This approach takes into account the general principles of surveillance described in Appendix 3.8.1. and the epidemiology of BSE. Because precise aging of the animals that are sampled may not be possible, Table 2 combines point values into five age categories. The point estimates for each category were determined as an average for the age range comprising the group. The age groups were selected on their relative likelihoods of expressing BSE according to scientific knowledge of the incubation of the disease and the world BSE experience. Samples may be collected from any combination of subpopulations and ages but should reflect the demographics of the cattle herd of the country, zone or compartment. In addition, countries should sample at least three of the four subpopulations. The total points for samples collected may be accumulated over a period of a maximum of 7 consecutive years to achieve the target number of points determined in Table 1. 2005 OIE Terrestrial Animal Health Code 14 Table 2 Surveillance point values for samples collected from animals in the given subpopulation and age category Surveillance subpopulation Routine slaughter * Fallen stock ** Casualty slaughter *** Clinical suspect **** age = 1 year and < 2 years 0.01 0.2 0.4 N/A Age = 2 years and < 4 years (young adult) 0.1 0.2 0.4 260 Age = 4 years and < 7 years (middle adult) 0.2 0.9 1.6 750 Age = 7 years and < 9 years (older adult) 0.1 0.4 0.7 220 Age = 9 years (aged) 0.0 0.1 0.2 45 * Article 3.8.4.2 4 ** Article 3.8.4.2 3 *** Article 3.8.4.2 2 **** Article 3.8.4.2 1 Surveillance points remain valid for 7 years (the 95th percentile of the incubation period). Article 3.8.4.5. To monitor the evolution of BSE in a country, zone or compartment once it is detected To monitor the evolution of BSE in a country, zone or compartment once it is detected, a more intensive sampling method needs to be used to determine disease prevalence. For countries that have determined that BSE exists within their cattle population, the goal of surveillance shifts from one of detection to one of monitoring the extent and evolution of the disease, and monitoring the effectiveness of control measures such as feed bans and SRM removal policies. 2005 OIE Terrestrial Animal Health Code 15 APPENDI X 3 . 6 . 3 . P R O C E D U R E S F O R T H E R E D UC TI O N O F I N F E C T I V I T Y O F T R A N S M I S S I B L E S P O N G I F O R M E N C E P H A L O P A T H Y A G E N T S Article 3.6.3.1. Meat-and-bone meal The following procedure should be used to reduce the infectivity of any transmissible spongiform encephalopathy agents which may be present during the production of meat-and-bone meal containing ruminant proteins: 1. The raw material should be reduced to a maximum particle size of 50 mm before heating. 2. The raw material should be heated under saturated steam conditions to a temperature of not less than 133°C for a minimum of 20 minutes at an absolute pressure of 3 bar. 2005 OIE Terrestrial Animal Health Code http://www.oie.int/downld/SC/2005/bse_2005.pdf EFSA Scientific Report on the Assessment of the Geographical BSE-Risk (GBR) of the United States of America (USA) Report Summary The European Food Safety Authority and its Scientific Expert Working Group on the Assessment of the Geographical Bovine Spongiform Encephalopathy (BSE) Risk (GBR) were asked by the European Commission (EC) to provide an up-to-date scientific report on the GBR in the United States of America, i.e. the likelihood of the presence of one or more cattle being infected with BSE, pre-clinically as well as clinically, in USA. This scientific report addresses the GBR of USA as assessed in 2004 based on data covering the period 1980-2003. The BSE agent was probably imported into USA and could have reached domestic cattle in the middle of the eighties. These cattle imported in the mid eighties could have been rendered in the late eighties and therefore led to an internal challenge in the early nineties. It is possible that imported meat and bone meal (MBM) into the USA reached domestic cattle and leads to an internal challenge in the early nineties. A processing risk developed in the late 80s/early 90s when cattle imports from BSE risk countries were slaughtered or died and were processed (partly) into feed, together with some imports of MBM. This risk continued to exist, and grew significantly in the mid 90’s when domestic cattle, infected by imported MBM, reached processing. Given the low stability of the system, the risk increased over the years with continued imports of cattle and MBM from BSE risk countries. EFSA concludes that the current GBR level of USA is III, i.e. it is likely but not confirmed that domestic cattle are (clinically or pre-clinically) infected with the BSE-agent. As long as there are no significant changes in rendering or feeding, the stability remains extremely/very unstable. Thus, the probability of cattle to be (pre-clinically or clinically) infected with the BSE-agent persistently increases. http://www.efsa.eu.int/science/efsa_scientific_reports/gbr_assessments/scr_annexes/563/sr02_biohaz02_canada_report_annex_en1.pdf MEXICO http://www.efsa.eu.int/science/efsa_scientific_reports/gbr_assessments/scr_annexes/566/sr04_biohaz02_mexico_report_annex_en1.pdf http://www.fda.gov/ohrms/dockets/dockets/03n0312/03N-0312_emc-000001.txt Docket Management Docket: 02N-0273 - Substances Prohibited From Use in Animal Food or Feed; Animal Proteins Prohibited in Ruminant Feed Comment Number: EC -10 Accepted - Volume 2 Greetings FDA, snip... PLUS, if the USA continues to flagrantly ignore the _documented_ science to date about the known TSEs in the USA (let alone the undocumented TSEs in cattle), it is my opinion, every other Country that is dealing with BSE/TSE should boycott the USA and demand that the SSC reclassify the USA BSE GBR II risk assessment to BSE/TSE GBR III 'IMMEDIATELY'. for the SSC to _flounder_ any longer on this issue, should also be regarded with great suspicion as well. NOT to leave out the OIE and it's terribly flawed system of disease surveillance. the OIE should make a move on CWD in the USA, and make a risk assessment on this as a threat to human health. the OIE should also change the mathematical formula for testing of disease. this (in my opinion and others) is terribly flawed as well. to think that a sample survey of 400 or so cattle in a population of 100 million, to think this will find anything, especially after seeing how many TSE tests it took Italy and other Countries to find 1 case of BSE (1 million rapid TSE test in less than 2 years, to find 102 BSE cases), should be proof enough to make drastic changes of this system. the OIE criteria for BSE Country classification and it's interpretation is very problematic. a text that is suppose to give guidelines, but is not understandable, cannot be considered satisfactory. the OIE told me 2 years ago that they were concerned with CWD, but said any changes might take years. well, two years have come and gone, and no change in relations with CWD as a human health risk. if we wait for politics and science to finally make this connection, we very well may die before any decisions snip... The general opinion of those present was that BSE, as an snip... It is clear that USDA have little information and _no_ regulatory snip... 3. Prof. A. Robertson gave a brief account of BSE. The US approach snip... http://www.bseinquiry.gov.uk/files/mb/m11b/tab01.pdf To be published in the Proceedings of the Evidence That Transmissible Mink Encephalopathy R.F. Marsh* and G.R. Hartsough •Department of Veterinary Science, University of Wisconsin-Madison, Madison, ABSTRACT INTRODUCTION Transmissible mink encephalopathy (TME) was first reported in 1965 by Hartsough OBSERVATIONS AND RESULTS A New Incidence of TME. In April of 1985, a mink rancher in Stetsonville, Wisconsin Experimental Transmission. The clinical diagnosis of TME was confirmed by DISCUSSION ACKNOWLEDGEMENTS REFERENCES MARSH http://www.bseinquiry.gov.uk/files/mb/m09/tab05.pdf TO think that a sample survey of 400 or so cattle in a population of 100 million, to think this will find anything, especially after seeing how many TSE tests it took Italy and other Countries to find 1 case of BSE (1 million rapid TSE test in less than 2 years, to find 102 BSE cases), should be proof enough to make drastic changes of this system. the OIE criteria for BSE Country classification and it's interpretation is very problematic. a text that is suppose to give guidelines, but is not understandable, cannot be considered satisfactory... http://www.fda.gov/ohrms/dockets/dockets/03n0312/03N-0312_emc-000001.txt http://brain.hastypastry.net/forums/archive/index.php/t-54550.html
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