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for all consumers BSE REPORT April 2005 Featuring: . Science news . General news . Official figures > BSE monthly report is compiled during the week following the month of the report. Material is collected from news reports, science abstracts and government sources, and is presented in good faith. However, Which? cannot guarantee the accuracy of the information and does not necessarily hold any of the opinions reported here. Readers are welcome to send correspondence to the editor at BSEREPORT@which.co.uk or by post to BSE monthly report, Policy Department, Which?, 2 Marylebone Road, London NW1 4DF. Science news Fragments of scrapie prion can self-replicate in test-tube Recent research has shown that truncated sections of the amyloid form of recombinant prion protein (PrP) encompassing residues 89-230 produced in test tubes can induce transmissible prion disease in mice (see January 2005 BSE monthly report). New research has now shown that these forms of prion are more proteinase-K sensitive but contain a proteinase K-resistant core composed only of residues 152/153-230 and 162-230.1 These PK-resistant fragments are similar to those observed upon PK digestion of a minor subpopulation of PrPSc recently identified in patients with sporadic CJD (sCJD). Remarkably, this core is sufficient for self-propagating activity in test-tubes, and preserves its beta-sheet-rich fibrillar structure. Furthermore, full-length recombinant PrP 23-230 when replicated in the test tube generates two distinct subpopulations of amyloid: one is similar to the minor subspecies of PrPSc, and the other to classical PrPSc. Since no cellular factors or templates were used for generation of the amyloid fibrils, the authors suggest that formation of the subpopulation of PrPSc with a short PK-resistant C-terminal region reflects an intrinsic property of PrP rather than the influence of cellular environments and/or cofactors. Experimentally-misfolded prions cause disease A further series of experiments has confirmed the ability of prions to transmit disease in isolation of other agents, with evidence that artificially misfolded prions can cause scrapie-like diseases when inoculated into test animals. Researchers in Texas have shown that the conversion of purified normal cellular prions PrPC into abnormal prions PrPres can be mimicked in test tubes using cyclic amplification techniques, giving rise to indefinite amplification of PrPres.2 The syntheticallygenerated forms of PrPres share similar biochemical and structural properties with PrPres derived from scrapie-infected brains. Inoculation of wild-type hamsters with the synthetically produced PrPres led to a scrapie disease identical to the illness produced by infectious material from brain. These findings, say the authors, demonstrate that prions can be generated synthetically and provide strong evidence in support of the prion-only hypothesis of disease transmission. GM mice can distinguish prion strains Genetically modified mice with genes able to express bovine prions have been developed in the laboratories of Nobel prize-winning scientist Stanley Prusiner.3 These mice show no apparent species barrier to BSE, with similar incubation times on first and second passaging of the disease. The mice also posed no transmission barrier for scrapie prions derived from Suffolk sheep, suggesting that cattle may be highly susceptible to some sheep scrapie strains. Furthermore, the mice were also found to be susceptible to prions from humans with variant CJD, although some species barrier appeared to be present, with incubation times shortened by 30 to 40 days on second passage. In contrast, the GM mice were not susceptible to sporadic, familial, or iatrogenic CJD prions. The structural stability of prions derived from cattle with BSE and from the GM bovine-mice with BSE were similar. The stability of sheep scrapie prions was higher than that found for the BSE prions but lower if the scrapie prions were passaged in 2 the GM mice. These findings suggest that BSE prions did not arise from a sheep scrapie strain like the one described here; rather, BSE prions may have arisen spontaneously in a cow or by passage of a different scrapie strain that maintains its stability upon passage in cattle. The authors suggest that it may be possible to distinguish BSE prions from scrapie strains in sheep by combining stability studies with studies using novel GM mice expressing a mixed mouse-bovine prion-encoding gene. Single-amino-acid substitutions in such mixed genes have produced large changes in incubation times that allowed the researchers to distinguish prions causing BSE from those causing scrapie, they state. Cellular prions detectable in urine A research team in Cleveland, USA, led by Dr Harash Narang, has demonstrated that normal cellular prions can be detected in human urine. The method "can easily and reliably" detect PrPC in apparently healthy individuals using less than 1 ml of urine.4 The amount of urinary PrPC is estimated to be in the range of several micrograms/litre. Dr Narang previously attempted to undertake research in Newcastle, UK, on the detection of BSE in urine, but research funding was withdrawn in the late 1990s in a move that caused some controversy at the time.5 Mouse prion infection is seen in spleen before brain An investigation of prion infection in mice by Japanese researchers has shown that the accumulation of the abnormal form of prion protein (PrPSc) in spleens occured far in advance of its accumulation in brains, whether the infection was initially administered through feeding, through injection into the abdomen (peritoneum) or injection directly into the brain.6 Using Western blotting with anti-prion protein antibodies, accumulation of PrPSc was first detected in the spleen on the 70th day after inoculation directly into the brain, and detected in the brain on the 116th day. Inoculation through the other routes took much longer to show the presence of PrPSc in either the spleen or brain (see table) but the spleen showed an accumulation of PrPSC at least 130 days in advance of it being detected in the brain. These results indicate that PrPSc increases rapidly in the spleen compared with the brain in a manner independent of the inoculation route. Number of days after inoculation with scrapie prion Inoculation route cerebral peritone al oral First detected in spleen 70 94 93 Maximum reached in spleen 116 94 93 First detected in brain 116 231 259 Maximum reached in brain 152 >231 >259 VLA provides kit to distinguish BSE from scrapie A discriminatory diagnostic kit to distinguish between scrapie and BSE in sheep has recently been launched by the Veterinary Laboratories Agency (VLA).7 Under EU legislation all samples from small ruminants that are positive for a TSE on rapid testing should be further screened using an approved discriminatory method to determine if BSE is present. Several methods have been evaluated and approved. The method developed by the VLA uses protein extraction and Western blotting 3 techniques to differentiate between scrapie and BSE. The new kit is a modified version of the Prionics-Check technique and is reported to provide ‘a cleaner, more defined signal of the abnormal prion protein profile' for analysis. Single use surgical instruments vary in quality Research undertaken to assess the quality and consistency of single-use adenotonsillectomy instruments available in the UK in comparison with reusable instruments has shown that the single-use instruments may vary in quality, with some samples proving to be significantly inferior to re-usable instruments.8 (This research study was presented at a SEAC meeting, March 2005.9) Following a detailed specification for single-use instruments, a surveillance system monitored the performance of samples of single use instruments in terms of the numbers of instruments from each set judged as unacceptable or as good as the original, and the number and cause of instrument failure during clinical surveillance. Between 40% and 93% of the instruments on each set were as good as the original and between 0% and 40% of the instruments were unacceptable, out of six sets of steel and one set of polymer instruments. Over 4000 procedures were monitored during 2003-2004 using a total of over 40,000 instruments. Problems were reported with 335 (0.8%) instruments, 46% attributable to instrument design, 14% to poor design control and 13% to instruments escaping quality control systems. Following correction of the faults, a survey in 2004 found the problem rate had fallen to 0.4%. The research team, in Wales, UK, concluded that high quality single-use instruments for tonsil and adenoid surgery are available in the UK, but that some companies offered inferior instruments not fit for their purpose. The procurement, introduction and subsequent clinical approval of single-use instruments requires a radically different approach to that currently applied to the purchase of reusable surgical equipment, they say. Careful monitoring of their introduction is essential. Disposable optical instruments carry bacteria In order to determine the pressure inside the eyeball, a small flat disk – an applanation tonometer – needs to be applied to the cornea. Due to the theoretical possibility of prion transmission in applanation tonometry, many ophthalmological units in the United Kingdom now use disposable tonometer prisms, but an investigation of the way in which these are applied suggest that they may become contaminated with bacteria before touching the eye.10 A questionnaire of staff revealed that almost 50% admitted touching the applanating face of the tonometer prism prior to applanation. Cultures of the prisms grew a range of bacteria including Staphylococcus epidermidis, Staphylococcus aureus, and Bacillus species. The results suggested that adenovirus could also be transmitted by applanation tonometry. The research team concluded that the use of disposable prisms may reduce the risk of prion transmission but is not bacteriologically or virologically aseptic. This is a potential infection risk to patients. Details given of French case of BSE in farm goat The Veterinary Record has published further details of the case of a goat tested under the surveillance programme and found to have BSE and not scrapie as first assumed when it was slaughtered in 2002.11 The case was found as part of a survey 4 re-assessing the cases of TSE, and consisting of seven French laboratories analysing 438 brain samples of suspected scrapie cases in sheep and goats, including 216 samples collected in 1990, 135 samples collected in 2002 and 87 cases collected in 2003. Three different Western blot tests and one ELISA test were conducted independently in four different laboratories, with each sample tested by at least three of the four tests. For one goat sample (CH636), the four tests provided convergent results, which were indistinguishable from those obtained with a control sample from an animal experimentally infected with BSE. When the brain extract was inoculated by the intracerebral route into four strains of wild-type mice, incubation times were all compatible with those recorded for experimental sheep BSE, and the lesion profile was identical to the profile characteristic of BSE in sheep. The researchers note that it is impossible to conclude whether the origin of the disease n the goat was linked to BSE-contaminated feed, or whether it reflects the presence of this strain of TSE in goats preceding the emergence of BSE in cattle. Nevertheless, they warn, the presence of this strain in a goat underscores the need to reassess the risks to human health linked to the consumption of small ruminant products. Sheep bred for hill farming most at risk of scrapie A large-scale survey of British sheep, involving 250,000 animals tested under the National Scrapie Plan between October 2001 and January 2003, has provided comprehensive data on the prevalence of scrapie resistant genotypes in 38 different breeds.12 The results showed marked variability among the genotype profiles of the different breeds, but several trends emerged. A comparison of the allele frequencies demonstrated that the breeds could be grouped into three categories: breeds dominated by ARR and ARQ in which the frequency of ARR exceeded the frequency of ARQ; breeds dominated by ARR and ARQ in which the frequency of ARQ exceeded the frequency of ARR; and breeds with significant levels of either AHQ, ARH or VRQ. Hill breeds were more likely to have a lower proportion of animals at low risk of scrapie (NSP type 1) and a higher proportion of animals at an intermediate risk of scrapie (NSP type 3) than other breeds. Most breeds had a small proportion of animals at high risk of scrapie (NSP type 5). The frequency of ARR/VRQ (NSP type 4) was variable. Sheep tongues infective in scrapie-infected animals The presence of infectivity in the tongues of animals infected with scrapie has been shown following either oral or intracranial inoculation with scrapie and with transmissible mink encephalopathy derived from laboratory rodents. A brief report from researchers in Turin, Italy, has stated that they have found scrapie-like prions in the tongues of seven scrapie-infected sheep, based on immunohistochemistry and Western blotting.13 Sheep blood tested for prion-carrying cells The blood of sheep infected with TSEs is known to carry infectivity. In an assessment of which cells may be most responsible for carrying this infectivity, researchers examined the expression of normal cellular prion (PrPC) in a variety of 5 sheep with different genetic resistance to scrapie.14 Expression of PrPC on the surfaces of cells was found only on peripheral blood mononuclear cells (PBMCs) although significant amounts of PrPC were found within platelet cells. The level of PrPC expressed on the cell surface of PBMCs was influenced by the scrapie-resistant genotype, with the highest levels found in scrapie-susceptible VRQ/VRQ sheep and the lowest levels in scrapie-resistant ARR/ARR sheep. In susceptible sheep, PrPC was expressed at varying levels on all major subsets of PBMCs, with the highest levels being found on the CD21(+) subset of B cells – and the level of expression was increased dramatically on these cells in some scrapie-infected sheep. Brain tissue may still be entering food supply Previous studies have demonstrated a potential risk of carcase contamination with brain tissue following the use of captive bolt gun stunning in cattle. A new study has now explored these findings in regard to the captive bolt guns currently in use in the United Kingdom.15 The research team, at Bristol University, found brain tissue fragments or elevated levels of a marker protein for brain tissue in venous blood samples from 4% (95% likelihood: 1.6% to 9.8%) of cattle stunned by penetrating captive bolt gun and from 2% (95% likelihood: 0.6% to 7%) of those stunned by the supposedly safer non-penetrating captive bolt gun. These methods of slaughter may give rise to Specified Risk Material entering the food supply. New antibodies may detect beef brain in cooked meats Because bovine central nervous tissue (CNT) is the main risk material in transmission of BSE, a test is needed to enforce the ban on CNT in human foodstuffs in many countries, including in the United States and the European Union. A German research team have used immunohistochemistry and Western blots with antibodies against glial fibrillary acidic protein (GFAP) and myelin basic protein (MBP), which are both resistant to processing methods used for meat products.16 The anti-GFAP antibody showed a high degree of tissue specificity, whereas the anti-MBP antibody had high species specificity, clearly differentiating between porcine and bovine CNT Therefore, say the researchers, immunochemistry performed with both antibodies in tandem could provide an effective means for detecting bovine CNT in meat products. Feline TSE: no hidden cases during the 1990s A survey of brain tissue from 192 cats with neurological signs has been undertaken to determine the prevalence of feline spongiform encephalopathy (FSE) during the peak of the disease during the early 1990s.17 Defra disease records show 81 reported cases of FSE in Great Britain, all recorded in the period 1990-1997. The research paper suggests that 89 cases were recorded in Great Britain and the Channel Islands since 1990, with single cases recorded in the years 1998-2001, and none since then. The present survey was based on animals referred to government veterinary laboratory services in the period 1990-1997. All cats were referred as suspected FSE, and originated in Great Britain apart from one sample from Norway. Prior to an animal’s death, the most commonly recorded clinical signs were ataxia, behavioural changes and epilepsy. All samples were examined histologically, and tissues from 173 of them were later examined immunohistochemically. 6 The results showed that none of the cats had histopathological evidence of FSE, but abnormal prion protein was observed in one of the cats examined by immunohistochemistry. Among the remaining cats, the most common findings were non-suppurative encephalomyelitis in 28 per cent, neoplasia in 15 per cent and a heterogeneous group of degenerative encephalopathies in 9 per cent of the cats. Statistical estimates put low risk on incinerator waste Researchers in Denmark have estimated that very low levels of infectivity would be found in the ash residues left after incineration of cattle meat and bone meal.18 At present, MBM is commonly incinerated in cement works or coal-fired power plants and the ashes and slag are incorporated into the cement or concrete. Using a statistical simulation model, the BSE risk to cattle and humans posed by the ash and slag was estimated, assuming that all specified risk material (SRM) and MBM produced in Denmark would be incinerated in a single gas-fired power plant operating at 850 degrees C. Assuming the incinerator handled up to six cases of BSE, and up to 31 carcasses or SRM from undetected BSE cases, then if the slag/ash was collected and re-incinerated for use in building material the resulting ash would contain less than one billionth of an infectious dose. Potentially infective tonsil tissue in cattle tongues Previous studies have shown that traces of infectivity were found in the palatine tonsil of cattle killed 10 months after exposure to BSE. Because the infectivity may therefore be present throughout the tonsils in cattle infected with BSE, observations have been made of the anatomical and histological distribution of tonsil tissue in the root of the tongue of cattle.19 Examinations of tongues derived from abattoirs in Britain showed that identifiable tonsillar tissue was present in more than 75 per cent of tongues destined for human consumption (as described as ‘ox tongue’). Even in the tongues in which no visible tonsillar tissue remained, histological examination revealed lymphoid tissue in more than 90 per cent. Variations in the distribution of the lingual tonsil suggested that even after the most rigorous trimming of the root of the tongue, traces of tonsillar tissue may remain. There is a risk that ox tongue on sale in the UK may contain infective material from pre-clinical BSE-infected cattle. NB A statement based on research similar to that reported in this paper was issued by the Food Standards Agency in June 2003 and discussed by SEAC that month. SEAC reviews risks from recent blood transfusions A meeting of the UK expert committee SEAC considered whether donated organs, such as bone marrow, would be infected if CJD-contaminated blood had been administered only hours before the donated organ was removed.20 It concluded that In the absence of robust and direct data it could be assumed that the vCJD agent is widely distributed within the body in the first 24-48 hours following a blood transfusion but may not necessarily have sufficient time to replicate to a significant extent. Thus, the infectivity level in a particular tissue/organ shortly after transfusion of infected blood may be dependent predominantly on some or all of the following factors: 7 • type of tissue/organ • possible clearance of infectivity • possible infiltration and retention of the vCJD agent in the tissue/organ • blood content of the tissue/organ • infectious dose in the transfused blood SEAC noted that relevant data on prion replication and spread following transfusion were extremely limited and mostly from animal models not directly applicable to the human situation. However, in the first few days following a transfusion with infected blood, significant prion replication was unlikely and, therefore, tissue prion levels would be related to the blood supply to the tissue in question. Highly vascularised organs such as liver, lung and spleen were more likely to contain the agent compared with other organs. The committee agreed that a balance must be struck between the small increased risk of prion transmission by transplant and the benefit to potential organ recipients of receiving a transplant, especially where tissues/organs are scarce. The committee noted that screening of cadaveric donors for the presence of abnormal prions prior to transplantation, washing tissues/organs to remove blood before their use, and avoiding the pooling of tissues may reduce transplant associated transmission risks. Estimated infectivity levels per unit whole blood Blood fraction Infectivity intravenous ID50/450mL contaminated whole blood unit Whole blood 900 of which Plasma 480 Buffy coat 201 Red blood cells 219 Red blood cells (leucodepleted) 2 No difference of risk between vertebra from 12-month and 30-month cattle The UK expert committee SEAC has stated that the difference in the BSE-related risk to the UK population from vertebral column derived from cattle aged either 12 or 30 months of age was negligible.21 The UK Food Standards Agency had asked SEAC to review an assessment of the possible UK exposure to BSE associated with vertebral column from cattle aged under 12 or under 30 months. The committee noted that some uncertainties remained with regard to the extent of the species barrier between cattle and humans although these uncertainties do not significantly affect the overall conclusions. Exposures had been calculated for the UK population, without considering whether a small subgroup within the population might consume most of the UK beef on the bone. Nevertheless, although exposure would be higher in consumers of beef on the bone than for the general population assumed in the study, it was considered that the increased risk to this population group would still be very small, and that the difference between the two age cut-offs for the specified risk material was insignificant. 8 HPA suggests epidemic passing The CJD quarterly review of the UK Health Protection Agency has suggested that the peak number of vCJD cases has passed.22 A graph of the dates of onset of disease show a peak at about 6 deaths per quarter in mid 2000 and has since declined to a current incidence of about 1.5 deaths per quarter. Extrapolating the best fitting model (the quadratic model) gives an estimate of 5 deaths in the next 12 months (95% prediction interval 1 to 11). The report warns that although a peak has been passed, it is possible that there will be future peaks, possibly in other genetic groups. There is also the possibility of ongoing person to person spread. 9 General news Canadian farmers claim damages for BSE Canadian cattle farmers have launched a C$7 billion (£2.9 billion) class action lawsuit against the Canadian government and an Australian-based feed maker for failing to prevent BSE in Canadian cattle.23 The lawsuit has been filed on behalf of more than 100,000 farmers from the provinces of Ontario, Quebec, Alberta and Saskatchewan, and claims that in the mid-1990s Ottawa lost track of 80 of 190 cows imported from Britain that it was supposed to be monitoring for BSE. The lost British cows were recycled into cattle feed and fed to other Canadian cattle, the lawsuit claims. Australian-based Ridley Corporation, through its Canadian subsidiary Ridley Inc which allegedly made the feed, should have known that it could have been contaminated by BSE, the lawsuit claims. ‘In 1996 they voluntarily stopped using cattle remains in cattle feed in Australia, and the Australian cattle industry remains BSE-free. But they didn't stop using it here,’ said Cameron Pallett, one of the lawyers representing the farmers. The Canadian government did not impose a ban on feeding cattle remains to cattle until August 1997. US farmers join USDA to re-open Canadian border The largest farm organization in the US – the American Farm Bureau – has joined the US Department of Agriculture's appeal of a court decision that is keeping the border closed to Canadian cattle.24 Nearly 30 other local farming bodies have joined the Bureau in support of the reopening of the border.25 In March, US District Judge Richard Cebull granted the Ranchers-Cattlemen Action Legal Fund (R-CALF) a temporary injunction to keep cattle out, just days before the USDA had planned to allow shipments to begin again. "There are many, many producers in the United States who do not agree with R-CALF, but their silence was a form of consent," said an AFB spokeswoman. No date has been set for the appeal court to hear the case. In July, Judge Cebull will hear arguments to determine whether the border reopens, remains closed or expands the temporary injunction to other Canadian beef products. The Alberta Beef Producers and Canadian Cattlemen's Association have applied for intervener status in the case. An earlier bid by the Canadian government to submit an amicus brief was denied. US continues to press Japan to lift import ban US trade representatives are continuing to put diplomatic pressure on Japanese authorities to lift Japan’s current ban on US beef imports.26 Rob Portman, US Trade Representative nominee, said that pressing Japan to quickly lift its 16-month-old import ban is his "top priority." Meanwhile Japanese meat hygiene authorities are investigating two suspected cases of BSE in cattle tested during April.27 Tissue samples were sent to the National Institute of Infectious Disease in Tokyo for more screening. They would mark Japan's 18th and 19th cases of BSE, if confirmed. US to put pressure on OIE to change standards The USA is expected to press for changes to the standards for beef trading at the World Animal Health Organization (OIE) during May.28 A set of standards was agreed 10 between the US, Canada and Mexico in March, and set nine conditions, including a requirement that exported beef must be from carcasses that have had the SRM removed at slaughter and a ban on imports of animals from herds with known cases of BSE. If the standards are adopted by the OIE, individual countries that attempt to maintain bans on imports from countries that comply with the standards may face legal challenge under World Trade Organization rules that prohibit unfair trading barriers. This might bypass the current negotiations between the US and Japan, forcing Japan to accept all US beef exports without any age or testing restrictions. The exact standards have not been published, but are reported to be based on the following guidelines: a definition of specified risk material and rules for removing it; a prohibition on exports of meat from non-ambulatory, disabled cattle; a prohibition on the use of pithing and air-injection stunning; a prohibition on the mechanical harvesting of meat from the skull and vertebral column of cattle over 30 months of age; import controls; surveillance guidelines; ruminant feed restrictions; improved cattle identification systems; and a four-part determination of risk status based on release, exposure, consequence and risk estimation.29 Meanwhile, the OIE is reported to be calling for strict curbs on beef trading of material at high risk of containing BSE contamination, such as brains, but has proposed easing trade restrictions on muscle separated from the bone, saying it is safe from BSE.30 The OIE is also reported to be circulating proposals to member governments to amend the BSE controls by changing the definition of bovine intestines under SRM guidelines.31 Japanese government officials said that the OIE is requesting that only certain parts of the intestine need to be designated as SRM, instead of the entire intestine. Details are not available from the OIE website. US welfare group opposes move to relax ‘downer’ rules Farm Sanctuary, a leading US farm animal protection organization, has condemned the Bush Administration's proposal to weaken the current ban on the slaughter of injured or ‘downer’ cattle for human consumption.32 In response to the first case of BSE in the USA in 2003, the USDA imposed a ban on the slaughter of all downer cattle for human consumption, but the new Bush proposal will allow certain cattle - - those with broken limbs and those which are under 30 months old – to enter the food chain. ‘This is misguided,’ said Farm Sanctuary president Gene Bauston, ‘because it ignores the fact that there are many disease-driven reasons that a cow may fall and break her limbs – including affliction with bovine spongiform encephalopathy.’ As part of a 2004 lawsuit settlement with Farm Sanctuary, the USDA acknowledged that ‘studies from Europe appear to show that non-ambulatory cattle, or "downed" cattle, have a greater incidence of BSE than other cattle, and, moreover, that the clinical signs of BSE cannot always be observed in cattle.’ In 2004, when the USDA requested public comments on the issue of downed cattle slaughter, the agency received 22,000 comments. Of these, ninety-nine percent supported an all-out ban on letting downer cattle into the food supply. The USDA’s new proposals were also condemned by consumer groups.33 Caroline Smith DeWaal, food safety director for the Center for Science in the Public Interest, said ‘Downer cattle represent less-healthy animals and should be kept out of the food supply.’ 11 USDA accused of faulty testing The US Agriculture Department has denied allegations from two former employees that faulty animal testing procedures may have kept officials from finding more cases of BSE in the United States.34 Former USDA veterinarians Lester Friedlander and Masuo Doi were quoted separately by Canadian news outlets saying that the United States may have more cases of BSE. Friedlander, who retired in 1995 as a food safety inspector in Pennsylvania, alleged that the USDA knew about the additional cases and was hiding the information. Agriculture Secretary Mike Johanns told reporters the USDA would not investigate Friedlander's allegation because he provided no proof. Dr. Masuo Doi, the USDA veterinarian in charge of investigating one of the 1997 cases, says he fears the right tests were not done and his own department did not properly investigate whether the cows had BSE.35 In one case, analysts did not test the part of the cow's brain most likely to show signs of BSE. In a second case, Doi was unable to obtain documentary evidence the animal was clear of BSE. Canadians urged not to adopt US meat inspection system Canada risks losing its independent testing and inspection capacity needed to protect the health and safety of Canadians if a proposed Food Inspection Agency Act is passed, according to Canadian and US experts who addressed the parliament’s House Standing Committee on Agriculture.36 Dr. Lester Friedlander, former USDA veterinarian and meat inspector, said ‘Rules and regulations are broken every day in the United States because the government is not enforcing them, allowing, for example, animal protein to be fed back to cattle.’ He has seen this occur in the US and believed it is a growing problem in Canada. He said ‘The public must insist that the food safety regulatory function be separated from the governmental agency promoting corporate agribusiness. We need a genuine, separate department of consumer protection.’ According to a civil advocacy group, the Council of Canadians, the proposed Act would allow the Canadian Food Inspection Agency to accept testing and certification results from other countries and is designed to harmonise with US regulations. However, the US system currently permits irradiation of meat, which is not allowed in Canada, has failed to meet World Health Organization guidelines for preventing BSE, and relies on voluntary compliance when companies are found in violation of its regulations. Furthermore, US whistle-blowing scientists who act in the public interest are not protected. ‘This government’s "Smart Regulation" legislative renewal project, which includes Bill C-27, is what I describe as the "Corporatization of Knowledge"— instituting private interests ahead of the public good,’ says Dr. Shiv Chopra, who along with colleagues Dr. Margaret Haydon and Dr. Gerard Lambert, blew the whistle on conflicts of interests in Health Canada’s drug approval process. ‘We will request the postponement of the entire legislative renewal process until after a full public inquiry into what we, as scientists, have been suffering on account of the pressure exerted on us to pass drugs and other products and methods of questionable safety.’ For more on the Council of Canadians, see http://www.canadians.org/ . 12 USDA approves Canadian BSE measures The US Department of Agriculture’s Animal and Plant Health Inspection Service (APHIS) have released a review of Canada’s BSE cases and control measures.37 The team found that Canada’s epidemiological efforts ‘were not only appropriate but exceeded levels recommended by an international team of BSE experts,’ said John Clifford, APHIS deputy administrator for veterinary services. The team reviewed Canada’s epidemiological investigations following four confirmed cases in Alberta and evaluated the possibility of a common source of exposure; the likelihood that other high-risk animals from Canada are currently present in the United States; and animal feed issues that may have led to exposure to US cattle. The team’s report concluded that the geographic and temporal proximity of the Canadian BSE cases suggests that they may have a common exposure point. The report also strongly suggests localized exposure through feed manufactured prior to the feed ban, or soon after its implementation. The team also noted that the Northwest region of the United States could be considered within a broadly defined movement area that could be at higher risk of exposure to BSE. BSE has cost US beef trade up to $5bn The Kansas Department of Agriculture has estimated that the US beef industry has lost between $3.2bn and $4.7bn in export revenues as a result of the BSE crisis.38 The report, prepared jointly with Kansas State University and entitled ‘The Economic Impact of BSE on the US Beef Industry’, notes that within days of the announcement that a cow in Washington state had been diagnosed with BSE in December 2003, 53 countries banned imports of US cattle and beef. In 2003, US beef exports were valued at $3.95 billion and accounted for 9.6 percent of US commercial beef production. Five countries – Japan, Mexico, South Korea, Canada and Hong Kong – received 90 percent of US beef exports in 2003. Mexico and Canada partially resumed beef imports in 2004, but overall the quantity of US exports fell by 82 percent below 2003 levels. The report evaluates the potential impact BSE testing could have if it were used to regain export markets. Researchers estimate that it would have cost about $640 million to test all cattle slaughtered in the United States in 2004, but that figure does not include any investment needed to place testing facilities in a beef processing plant. Regulations issued in 2004 by USDA's Food Safety and Inspection Service had an estimated net cost to the beef industry of approximately $200 million, plus some one-time investments that were substantial, but varied widely from firm to firm. Those costs related to the inability to market non-ambulatory cattle, the need to age cattle presented for slaughter, to segregate and process separately cattle older than 30 months and to prevent certain tissues from entering the food supply. The study also examined potential costs related to feed regulations being considered by the Food and Drug Administration. Last July, FDA published an advance notice of proposed rulemaking seeking input on regulation changes the agency was considering to ban from cattle feed all bovine blood products, plate waste and poultry litter, and to require dedicated equipment for producing ruminant and non-ruminant feed to prevent cross-contamination. To date, FDA has not made the rules final. The report is available online at http://www.agmanager.info/livestock/marketing/bulletins_2/industry/default.asp 13 Germany finds BSE in animal born 2001 German veterinary authorities have reported a case of BSE in an animal born in May 2001, German news agencies have reported.39 Meat and bone meal was prohibited in cattle feed the previous year. New York authorities find CWD in wild deer A systematic hunt to determine whether CWD has spread from two Oneida County deer farms has been launched in New York state with the erection of a field laboratory and the start of a sampling regime that will collect more than 400 wild deer in a ten mile radius of the farms.40 By the end of April one wild white-tail deer had been identified as a possible positive case.41 New regulations will require hunters who kill deer in Oneida County and parts of Madison County to be passed by state checkpoints.42 Samples will be taken for testing from deer killed by hunters and from deer involved in motor vehicle accidents. In March, a 6-year-old white-tailed doe from an Oneida County farm tested positive for the disease, becoming the first known case east of Illinois. Four other captive deer on another nearby farm have since tested positive. One of the first NY deer to test positive had been served at a meeting of 350 people at a reunion dinner. Texas CWD expert Professor Tam Garland said that there was no evidence that CWD could spread to humans, but that the dinner had provided an opportunity to do an epidemiological study.43 A state health department spokesman said that although no medical studies are planned, the Oneida County health department has a list of those who ate the infected deer. The people can be quickly contacted if the need arises. North Carolina proposes ban on deer as pets The North Carolina Wildlife Resources Commission (NCWRC) has said that the majority of households that keep elk, white-tailed and mule deer, do so for ‘family companionship’ and that a ban on new licenses for captive deer may help to thwart the spread of CWD.44 Kelly Douglass, captive cervid program leader for the NCWRC, said that although there was no documented case of CWD in North Carolina yet, the Commission was to hold a public hearing in May on prohibiting future captivity licenses in an attempt to prevent the disease from spreading to the State. During the five-year incubation of the disease ‘the animals show no signs of illness but are contagious and can infect other animals,’ she said. A court in Tennessee has upheld the state’s right to ban the keeping of deer.45 The law had been introduced in Tennessee in 1991 as a disease control measure, but has been challenged by traders and hunters three times since then. DEFRA changes Scrapie Flocks Scheme Amendments to the controls on scrapie-affected farms under the Compulsory Scrapie Flocks Scheme have been announced by the UK Department for the Environment, Food and Rural Affairs (DEFRA).46 The scheme, which applies control measures to farms where a case of scrapie is confirmed, has been amended following changes to EU legislation. The amendments are: 14 • An extension from three to five years of the period in which derogations to delay culling can apply for breeds or flocks with low levels of resistant alleles or at risk of inbreeding; • Lambs of specified genotypes will be allowed to be moved from scrapieaffected flocks for fattening for slaughter; • Controls can now be applied to the individual flock on a farm based on a veterinary assessment; • Official movement restrictions can now be placed on sheep and goats on farms when a case of scrapie is suspected rather than when it is confirmed; As of March 18, there were 113 flocks (involving 64 holdings) in the scheme, which is operated under the National Scrapie Plan for Great Britain. DEFRA said it would continue to keep the operation of the scheme under review and would press for other amendments to EU legislation when this was necessary. 84 countries maintain ban on British beef Eighty-four countries, including the United States, India and Australia, still have a ban on the import of British beef, after the BSE crisis. A spokesperson for the Department for the Environment, Food and Rural Affairs said the reasons cited for the bans were ‘animal and public-health related’.47 Meanwhile the European Commission has so far not moved to downgrade the UK’s risk rating from ‘high’ to ‘moderate’ despite a statement from the European Food Safety Authority’s expert Panel on Biological Hazards that the UK now conforms to the definition of ‘moderate’ risk under the OIE’s definitions, announced in March.48 The OIE threshold for a country to be considered moderate risk in terms of BSE is set at 200 BSE positives over a 12 months period per 1 million adult cattle (aged over 24 months). Irish oxtongues broke SRM rules The UK Meat Hygiene Service (MHS) has reported finding six consignments of fresh beef tongues, 192 tongues in total, exported to the UK from the Republic of Ireland, which have not been harvested in accordance with the TSE Regulations that require tongues be removed in such a way as to minimise the risk of lingual tonsil (which is SRM) remaining attached to the tongue. The breaches were discovered on the 23 and 24 February and the 1 and 8 of March 2005.49 Illegal slaughterer jailed for six months A farmer caught operating an illegal slaughterhouse at his remote small-holding in the north-east of Scotland was jailed for six months this spring,. The operation is believed to be part of a highly-organised criminal network that poses a risk to public health.50 Julian Jones, 41, was jailed for six months at Elgin Sheriff Court after he was arrested for his part in an illegal operation to supply outlawed sheep smokies – a Caribbean and West African delicacy – to ethnic communities throughout England. Arresting officers found the carcasses of 62 sheep that had been slaughtered by having their throats slit and left to bleed to death in a filthy, faeces-strewn barn. Most of the animals had not been stunned before having their throats slit. Some of the carcasses contained parts of the spinal cord and spleen, material that should be removed as part of the control measures to prevent the risk of BSE infection. 15 Netherlands reports first vCJD case, France adds 2 more The Dutch government has reported the country’s first case of vCJD in April, but stated that Dutch beef is safe to eat due to the safety control measures introduced over the last decade.51 The patient was reported to be a 26-year-old woman from Utrecht and has been neither a donor nor recipient of blood or tissue. She has never lived outside of the country, and the presumed source of her infection is contaminated beef.52 There have been more than 70 BSE cases in animals in the Netherlands since 1997, but the government said that ‘all susceptible cattle are now tested for BSE at slaughter’. The Netherlands is one of the world's biggest exporters of meat and dairy products and its livestock sector has undergone major intensification in the past few years with most animals raised on specialised farms. Meanwhile, French authorities are reported to have announced two more cases of vCJD, bringing the total to four over the last half-year, and 11 cases in total for the country.53 The two individuals diagnosed with vCJD ‘are not on the records as having been blood donors,’ the Institute of Health Surveillance (InVS) said in a statement. Japanese fear blood shortages The Japanese Ministry of Health has said that the country’s medical facilities are facing an unprecedented blood shortage and may start running out in some areas.54 The Health, Labor and Welfare Minister, Hidehisa Otsuji, was filmed on the streets of Tokyo urging ‘teenagers and those in their 20s’ to donate blood. According to the Japanese Red Cross Society, blood supplies are normally lower in March and April each year because student donors are away for spring break and office workers are busy closing their books for the fiscal year at the end of March. The amount of overall blood available has also dropped in recent years due to the declining birth rate. However, the government's recent proposal to tighten controls on donations from people who have travelled to Britain may also be having an effect. At one point the stock of red blood cells -- a gauge of blood supply -- stood at 74 percent of normal, defined as the level sufficient for meeting demand for a period of three days, the Red Cross said. Supply in the Tokyo area dropped to 64 percent. Anything below 70 percent indicates supplies may run out during major disasters or other high-demand crises. Last month, the ministry concluded that the first Japanese patient to die from the vCJD had probably been exposed during a stay in Britain or France during the 1990s. People who stayed in Britain or France for at least six months since 1980 have already been banned from giving blood, according to the Red Cross. The ban was tightened last February to cover those who were in Britain for at least one month. The restrictions on people who travelled to France have remained unchanged. Plans to tighten the rules to exclude anyone who visited Britain for as little as a day were due to take effect in May but may be delayed while blood stock levels recover. Confusion over fate of NIH brain samples A US health official who had previously said that a collection of human brain tissues might be destroyed has subsequently been reported as saying the samples will be 16 preserved.55 The collection of frozen samples held by the National Institutes of Health (NIH) contains brains and other tissues from hundreds of people who died from CJD. The NIH official, Eugene Major, acting director of the basic neuroscience program, told United Press International (UPI) in March the collection would be destroyed. The remaining collection ‘has very little remaining value’ and could be destroyed if another entity does not claim them, he said. Subsequently Florence Kranitz, the president of the CJD Foundation, a non-profit patients' advocacy group, said that Major had told her that the remaining tissues in the collection would be preserved. UPI reports that Major has not responded to emails or a phone call from UPI seeking clarification of his alleged remarks. Public-private co-funding for UK’s vCJD treatment research GlaxoSmithKline Plc, Europe's biggest pharmaceutical company has joined with the UK Medical Research Council and the UK Department of Health to co-fund a research programme to search for treatments for vCJD.56 The company will provide its library of drug compounds, allowing the research team to screen the molecules for their potential activity against the infectious proteins that cause TSEs in humans and animals. ‘Many person-years of very difficult work at the MRC have been invested to get to the stage where development of a drug to completely block prions appears realistic,’ Dr John Collinge, director of the MRC Prion Unit and head of the Department of Neurodegenerative Disease at University College London, said. The first phase of the work to find a possible treatment may take six years, the MRC said. ‘Last’ of the dura mater CJD cases A coroner’s court has been told that a case of CJD caused by the use of contaminated dura mater could be the last to occur in the UK.57 The dura mater – a membrane surrounding the brain obtained from a donor corpse – had been stored with other samples, one of which may have been contaminated. It was determined to be the cause of death of Mr Simon Stratford, a father-of-four from St Neots in Cambridgeshire, in 2003. Mr Stratford, 34, had the repair patch inserted into his head after surgeons removed a tumour on his skull in 1987. The material, known as a Lyodura patch, was withdrawn from sale by the manufacturers, West German company B Braun, over a decade ago, after 900,000 patches had been produced world-wide during a 28-year period. Professor Robert Will, consultant neurologist at the Western General Hospital in Edinburgh, told the inquest that 168 patients had contracted CJD after having some kind of graft onto the membrane surrounding their brains, seven of which were in the UK. He said CJD contracted during this form of surgery emerged, on average, nine years later, with the longest incubation period being 22 years. He said ‘We think that the majority of cases have emerged by now. There is no reason to think there is going to be great numbers of cases emerging in the future. Mr Stratford may well be the last victim in the UK.’ After the hearing in Huntingdon, Mr Stratford's widow Colleen, 37, said she was considering legal action. A verdict of misadventure was recorded by the coroner. 17 Blood transfusions may prevent organ donation Transplant services may restrict the surgical use of tissues from patients who have undergone blood transfusions to protect recipients from the small risk of vCJD.58 The availability of bone, skin, tendons, ligaments, corneas and heart valves could be hit, although some other organs, and bone marrow, may not be included as supplies are already insufficient. Anyone who has had blood transfusions since 1980 is already banned from donating blood following strong evidence that two people have been accidentally infected through transfusions. This has led to a fall of 5-10% in potential donors. Now safety advisers and tissue banks want to balance the risks and benefits on tissue donation, although no decisions are likely until the autumn. Health officials want to establish how many transplant donors have had blood donations either years before or in the week leading up to their deaths. Many are likely to have done so, since they are often victims of road or other accidents or haemorrhages, who will have received highly intensive care. The expert advisory committee, SEAC, has suggested that for most organs the risk of transmitting vCJD may be less if the donor only received a transfusion in the preceding days – which may mean organ supplies might not be hit as seriously as if all donors who had received transfusions were barred from donation. People needing new hearts, lungs, kidneys or livers are often so ill that the benefit of a transplant would far outweigh even the slight risk of infection by the CJD family of diseases. More than 6,000 people are awaiting organ transplants, yet last year 1,244 donors, most of them dead, supplied fewer than 2,850 organs. [See ‘Science’ section above for further details of SEAC’s view on transfusions prior to organ donation.] 18 Official figures BSE The figures below are derived from the OIE59, national authorities and news sources60. The figures include cases from farmers’ and vets’ reports (passive surveillance) and cases discovered during testing of at-risk animals, fallen stock or animals entering the food chain (active surveillance). Reported cases of BSE Includes passive and active surveillance cases country total BSE cases since 1986 total in 2005 reported by 1 May 2005 Great Britain 180 776 69 Isle of Man 437 0 Guernsey 700 0 Alderney 2 0 Jersey 150 0 Northern Ireland 2 139 7 GB and NI total 182 915 76 Azores 5 0 Austria 1 0 Belgium 130 1 Canada 4 1 Czech Republic 18 3 Denmark 14 0 Falkland Islands 1 0 Finland 1 0 France 960 14 Germany 378 15 Greece 1 0 Ireland 1507 24 Israel 1 0 Italy 129 3 Japan 19 5 Liechtenstein 2 0 Luxembourg 2 0 Netherlands 77 0 Oman 2 0 Poland 31 11 Portugal 965 13 Slovakia 19 0 Slovenia 5 0 Spain 542 27 Switzerland 457 1 United States 1 0 NB Reported cases from active surveillance are based on sampling criteria which differ between member states, with some states testing additional categories to those required under EU law. BSE testing of healthy cattle The testing of healthy adult cattle aged over 30 months entering the food chain or for surveillance purposes is required under EU regulations. However, country-tocountry comparisons need to be treated cautiously. Some countries test some categories of animals from age 24 months. The sample sizes vary greatly, with higher margins of error for the smaller samples. The ages at which animals are typically sent for slaughter will also affect the likelihood of finding disease. Most older cattle are dairy cows past their peak milk yields. In larger herds the cattle may be sent for slaughter shortly after their yields start to fall, whereas in smaller herds the cattle may be kept longer as the replacement cost represents a relatively large amount of capital expenditure. Thus, in countries that generally have small herd sizes, the cattle may be kept for longer on the farm and the chances of BSE cases developing will be higher. Tests on healthy cattle subject to normal slaughter61 Jan-Dec 2003 Jan-Dec 2004 Country Tests on healthy cattle Positive cases Cases per million tests Tests on healthy cattle Positive cases Cases per million tests Austria 205 659 0 0 188 538 0 0 Belgium 356 184 10 28 356 813 6 17 Denmark 250 359 1 4 244 902 0 0 Finland 108 207 0 0 107 614 0 0 France 2 920 157 37 13 2 624 634 17 6 Germany 2 337 605 23 10 2 251 062 34 15 Greece 24 533 0 0 26 161 0 0 Ireland 600 586 31 52 605 386 20 33 Italy 648 894 15 23 851 014 2 2 Luxembourg 14 598 0 0 13 575 0 0 Netherlands 439 403 11 25 467 448 5 0 Portugal 81 633 44 543 78 783 21 267 Spain 453 772 75 166 468 984 37 79 Sweden 9 856 0 0 10 318 0 0 UK 242 827 19 79 341 708 10 29 Total EU-15 8 694 273 266 31 8 636 940 152 18 Cyprus 6 401 0 0 5 888 0 0 Czech Repub 133 046 3 23 130 124 2 15 Estonia 21 277 0 0 Hungary 7 102 0 0 80 528 0 0 Latvia 4 838 0 0 28 017 0 0 Lithuania 7 418 0 0 47 506 0 0 Malta 1 089 0 0 2 067 0 0 Poland 428 452 4 9 446 770 8 18 Slovakia 65 192 1 15 63 553 5 79 Slovenia 54 751 0 0 35 767 0 0 Total EU-25 9 402 562 274 29 9 498 437 167 18 Norway 9 804 0 0 10 437 0 0 Bulgaria 7 789 0 0 20 BSE testing of sick animals The testing of cattle fallen ill at the farm or in transit, or those presenting as ill at the abattoir, aged over 24 months, is required under EU regulations. Positive test results on suspect, at-risk and cohort cattle62 Jan-Dec 2003 Jan-Dec 2004 Country Cohort animalsa Cattle at riskb Suspected casesc Cohort animalsa Cattle at riskb Suspected casesc UK 0 404 184 0 234 91 Total EU 15 9 777 306 5 493 174 Total accession 0 0 1 0 12 0 Norway 0 0 0 Bulgaria 0 0 0 a = Animals born or reared with BSE cases, offspring of BSE cases, animals from herds with BSE. b = Dead-on-farm, emergency slaughtered, sick at ante-mortem inspection. c = Animals reported as BSE clinical suspects ( = passive surveillance). BSE in Britain GB: Confirmed BSE cases63 year BSE suspected cases new herds to end 1987 675 333 1988 2 184 1 918 1989 7 137 3 391 1990 14 181 4 478 1991 25 032 5 817 1992 36 682 7 266 1993 34 370 5 790 1994 23 945 2 654 1995 14 302 1 401 1996 8 016 764 1997 4 313 483 1998 3 180 399 1999 passive reports: 2 258 active testing: 18 248 2000 passive reports: 1 311 active testing: 44 169 2001 passive reports: 781 active testing: 332 124 2002 passive reports: 445 active testing: 594 93 2003 passive reports: 173 active testing: 374 46 2004 passive reports: 82 active testing: 226 12 2005 to mid-April passive reports: 10 active testing: 59 0 Total reported passive 179 129 active 1 647 35 403 21 The incidence of BSE is falling, but against this decline in the number of cases must be set the possibility that cattle carrying BSE have been slaughtered before showing the disease, under the following schemes: • the Selective Culling scheme which, from early 1997 to mid-2002, removed over 77,300 UK cattle at greatest risk of developing BSE based on their herd and feeding histories.64 • the Over Thirty Month slaughter scheme which, from April 1996 to June 2004, has removed over 7.3 million older cattle from the national herd, a rate of about 8% of cattle each year (19% of adult animals),65 in addition to an unspecified number of older cattle culled under the foot and mouth disease culling regime. • the BSE Offspring Cull, which since October 1998 has identified over 32,600 offspring of BSE cases that have been, or will be, slaughtered. Currently 50 of the animals are awaiting slaughter and 158 are deemed untraceable. Infection rates Figures for Great Britain show: • Proportion of cattle herds affected with BSE: 38.5% of which • Proportion of dairy herds affected: 62.0% • Proportion of beef suckler herds affected: 17.5% Annual incidence among cattle aged over 24 months: • Great Britain: 53.3 cases per million (Mar 04 - Feb 05) • Northern Ireland: 31.5 cases per million (Mar 04 - Feb 05) Since the emergence of the BSE epidemic in 1986, the large majority of animals diagnosed with BSE have not shown the disease until they were aged over 30 months old. However, cases of clinical BSE were found in animals aged 30 months or younger every year from 1986 through to 1996. • Youngest confirmed case aged 20 months • Second youngest case aged 21 months • Eleven cases reported aged under 25 months Since the year 2000, the youngest case has been an animal born in October 2001 and aged 39 months at slaughter (see next section). BSE cases born after the 1996 feed ban The majority of UK BSE cases now being reported were born after the 1988 ruminant protein ban, which had been introduced to prevent the further spread of the disease. The clear failure of those regulations led to more stringent measures, applied in mid-1996, in which all mammalian meat and bone meal was banned from ruminant feeds (subject to some loopholes). However, since that later date several animals have been born that subsequently developed BSE. These animals are sometimes referred to as BARB cases, i.e. cases Born After the Reinforced Ban. In the UK, 115 cases of BSE have been detected in BARB animals, 100 cases in Great Britain and 15 in Northern Ireland.66 This includes the first case of a BARB animal born in 2001. 22 BARB cases, GB and NI cases confirmed by 1 May 2005 date of birth confirmed cases, passive reported confirmed cases, active surveillance Aug-Dec 1996 5 15 1997 13 32 1998 8 22 1999 3 13 2000 1 2 2001 0 1 Total after 01/08/96 30 85 Whether these cases have been the result of insufficient enforcement of the feed ban, or because maternal transmission has perpetuated the disease or because there are other agents that have not been fully controlled controlled, has not been determined. A review of the BARB cases up to early November 2003 found no evidence for maternal transmission and no evidence that BARB cases were transmitted environmentally e.g. in high-incidence herds or from abattoir waste.67 Questions remain about other factors, such as the use of artificial colostrum and the content of weaning feeds, and the continued potential contamination of feed in mainland Europe before strict controls were introduced in 2001. TSEs in sheep and goats Testing of sheep and goats for TSEs is required under EU regulations. Results of the testing programme of animals at risk (fallen stock, suspected cases etc) and healthy animals are reported below: Tests on sheep and goats at risk EU15, January-December 200368 Number of tests of sheep Positive cases Number of tests of goats Positive cases Eradication – cohorts and offspring of cases 30 950 872 4 495 12 Sick and fallen animals 106 061 115 21 004 6 TSE clinical suspects 1 214 517 92 11 EU 15 total at-risk 138 324 1 504 25 591 29 EU25, January-June 200469 Number of tests of sheep Positive cases Number of tests of goats Positive cases Eradication – cohorts and offspring of cases 13 331 472 1 196 24 Sick and fallen animals 86 758 111 9 720 7 TSE clinical suspects 383 196 115 15 EU 25 total at-risk 100 472 779 11 031 46 Norway 2 929 6 76 0 23 Tests on healthy sheep and goats January-December 200370 Number of tests of healthy sheep Positive cases Number of tests of healthy goats Positive cases UK 72 518 46 193 1 EU 15 total 341 241 236 35 947 16 Norway 33 520 5 1 610 0 Slovakia 3 924 1 4 0 January-June 200471 Number of tests of healthy sheep Positive cases Number of tests of healthy goats Positive cases UK 2 975 2 12 0 EU 25 total 65 748 45 6 074 1 Norway 4 423 3 20 0 Scrapie in Britain Data on scrapie in sheep and goats have been collected since the disease became notifiable in 1993.72 Not all cases were confirmed until compulsory slaughter legislation was introduced in 1998. Interpretation of trends before 1998 may therefore be unreliable. Scrapie cases (Great Britain) confirmed pending or inconclusive 1993 328 3 1994 235 2 1995 254 1 1996 460 3 1997 508 4 1998 499 1 1999 598 2 2000 568 0 2001 295 9 2002 427 1 2003 439 10 2004 333 9 2005 to 31 January 21 12 Active surveillance for scrapie undertaken in Britain since 2001 has found 133 cases in sheep out of more than 129 000 tested, and one case among more than 600 goats tested. 24 CJD One hundred and fifty-five cases of vCJD had been reported in the UK by early April 2005 including five probable cases currently alive. Outside of the UK, there have been eleven cases in France (one of which was probably due to the ingestion of bovine pituitary extract as a sports dietary supplement), two cases in the Republic of Ireland (one with a history of UK residency), one case in the USA (with a history of UK residency), one case in Canada (with a history of UK residency), one case in Italy (no history of UK residency) and one case in Saudi Arabia (possible history of UK residency).73 A case in Hong Kong has been included in the UK numbers because of a history of long term UK residency.74 A case in Japan was confirmed as vCJD in February 2005.75 A suspected case of vCJD is being investigated in Morocco.76 A suspected case is being investigated in the Netherlands.77 UK suspected CJD (referrals)78 CJD referrals 1996 134 1997 161 1998 154 1999 170 2000 178 2001 179 2002 163 2003 162 2004 112 2005 to 29 April 31 UK CJD deaths79 Probable and confirmed vCJD Sporadic CJD Other CJDs 1990 -- 28 5 1991 -- 32 4 1992 -- 45 8 1993 -- 37 9 1994 -- 53 8 1995 3 35 9 1996 10 40 10 1997 10 60 11 1998 18 63 8 1999 15 62 8 2000 28 50 4 2001 20 58 9 2002 17 72 5 2003 18 77 11 2004 9 49 6 2005 to 29 April 2 10 1 Total since 1990 150 771 116 UK: Suspected vCJD cases alive: 5 25 Abbreviations BAB = Born After the Ban -- cattle which born after the ban on the inclusion of mammalian meat and bone meal (MMBM) in cattle feed introduced in 1988. This ban has subsequently been shown to be inadequate at preventing the use of MMBM in feed. BARB = Born After the Real Ban – cattle born after the more stringent ban on the use of mammalian mat and bone meal, introduced in August 1996. BSE = Bovine Spongiform Encephalopathy, a disease of cattle first recognised circa 1986. CJD = Creutzfeldt Jakob Disease, a human form of spongiform encephalopathy. CWD = Chronic Wasting Disease, a TSE found in elk and deer in mid-west USA. DEFRA = UK Department for the Environment, Food and Rural Affairs (absorbed MAFF). DoH = UK Department of Health. EC = European Commission, the executive arm of European governance. FSA = UK Food Standards Agency. MAFF = UK Ministry of Agriculture, Fisheries and Food (incorporated into DEFRA in 2001). MBM = Meat and bonemeal, made from rendered carcasses and once used in highprotein animal feed. MMBM = Mammalian MBM. Under EU regulations, this is not permitted to be fed to ruminant mammals. MRM = Mechanically Recovered Meat, scraped from bones and connective tissue. OTM = Over Thirty Month scheme in the UK prohibiting older cattle from the food chain. PrP = The prion protein PrPC = Normal cellular prion PrPres = Abnormal prions, defined by resistance to degradation with protein enzymes. PrPSc = Abnormal prions, presumed to be similar to those found in scrapie. SBO = Specified Bovine Offal, cattle offal prohibited from human food supplies. SEAC = the Spongiform Encephalopathy Advisory Committee, a UK governmentappointed expert advisory group. SRM = Specified Risk Material, ruminant offal prohibited from human food supplies. SSC = the Scientific Steering Committee, an EC-appointed expert advisory group. TSE = Transmissible Spongiform Encephalopathy, a general term for the family of diseases including BSE, scrapie, CWD and vCJD. vCJD = the new form of Creutzfeldt Jakob Disease which has been linked to BSE in cattle. (The ‘v’ stands for ‘variant’ or ‘new variant’.) 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CDSC Statistics Unit, Health Protection Agency. 14 April 2005. 23 The Canadian / AAP, 12 April 2005. 24 CBC / Alberta News, 25 April 2005. 25 B Gorham, Canada Press / Canada.com, 26 April 2005. 26 The Japan Times, 23 April 2005. 27 I Morita, Bloomber.com, 18 April 2005. 28 The Japan Times, 6 April 2005. 29 Agriculture Online (www.agriculture.com) 4 April 2005. 30 The Japan Times Online, 9 April 2005. 31 Kyodo news agency, 5 April 2005. 32 US Newswire, 20 April 2005. 33 R Fabi, Reuters / Yahoo News, 15 April 2005. 34 Reuters, 13 April 2005. 35 United Press International, 13 April 2005. 36 Council of Canadians and Beyond Factory Farming, joint news release, Canada Newswire, 12 April 2005. 37 U.S. Department of Agriculture’s Summary of the Epidemiological Findings of North American, USDA, April 2005. See http://www.aphis.usda.gov/lpa/issues/bse/bse_epi_report_4-29-05.doc . Bovine Spongiform Encephalopathy Positive Cattle 38 L Taylor, Kansas Dept of Agriculture, Agriculture Online, 28 April 2005. 39 A Brodmerkel, Berliner Zeitung, 8 April 2005. 40 J Carleo-Evangelist, NY Times Union, 21 April 2005. 41 United Press International, 28 April 2005. 42 Newsday.com / Associated Press, 29 April 2005. 27 43 NBC / Associated Press, 18 April 2005. 44 E Beckley, Outer Banks Sentinel, North Carolina, 4 May 2005. 45 Tennessean.com, 5 May 2005. 46 News and Reports, The Veterinary Record 156:426-427, 2 April 2005. 47 The Scotsman (Scotsman.com), 6 April 2005. 48 Statement of the BIOHAZ Panel RE : Technical Advice on the United Kingdom application for application of Moderate Risk in terms of Bovine Spongiform Encephalopathy (BSE), Statement of the Scientific Panel on Biological Hazards, EFSA 15 March 2005. See http://www.efsa.eu.int/science/biohaz/biohaz_documents/catindex_en.html . 49 Food Standards Agency, Monthly report of Specified Risk Material and other BSE Control breaches for March 2005, 20 April 2005. 50 F Urquhart, The Scotsman / Scotsman.com, 19 April 2005. 51 E Thomasson, Reuters / Swissinfo, 21 April 2005. 52 Associated Press / Las Vegas Sun, 21 April 2005. 53 Agence France Presse / Khajeel Times, 5 April 2005. 54 The Japan Times, 10 April 2005. 55 United Press International, 7 April 2005. 56 A Zimm, Bloomber.com, 12 April 2005. 57 BBC News Online, 13 April 2005. 58 J Meikle, The Guardian, 22 April 2005. 59 Office International des Epizooties [www.oie.int] 60 An excellent source is J Braakman [www.bovine.nl]. 61 European Commission website, [http://europa.eu.int/comm/food/fs/bse/testing/bse_results_en.htm] 62 European Commission website, [http://europa.eu.int/comm/food/fs/bse/testing/bse_results_en.htm] 63 DEFRA BSE Information, Weekly statistics. 64 For details of this programme, see K Taylor, MAFF Programme to Eradicate BSE in the United Kingdom, in The Mad Cow Crisis (S C Ratzan, Ed), UCL Press, London, 1998. 65 MAFF gave figures for UK cattle herds as totalling 10.878m head in 2000 (11.281m in 1999, and 11.237m in 1998) Agra Europe Weekly, 30 March 2001. Adult cattle total some 5.3m in 2001, according to the table of figures on testing of animals, FSA Press Release 2001/0132, 3 August 2001. 66 BSE: Measures taken by the UK, DEFRA Monthly Report, and subsequent DEFRA notices. 67 Paper 80/4, SEAC meeting, London, 26 November 2003. 68 European Commission website, [http://europa.eu.int/comm/food/fs/bse/testing/bse_results_en.htm] 69 European Commission website, [http://europa.eu.int/comm/food/fs/bse/testing/bse_results_en.htm] 70 European Commission website, [http://europa.eu.int/comm/food/fs/bse/testing/bse_results_en.htm] 71 European Commission website, [http://europa.eu.int/comm/food/fs/bse/testing/bse_results_en.htm] 72 DEFRA, www.defra.gov.uk/animalh/bse/bse-science/level-4-scrapie.html, Incidence of Scrapie. 73 J Ironside, CJD Surveillance Centre, Statement to SEAC meeting, London, 3 March 2005. 74 H Ward, National CJD Surveillance Unit, Statement to SEAC meeting, London, 25 February 2004. 75 Reuters, 4 Feb 2005. 76 Reuters, 4 March 2005. 77 E Thomasson, Reuters / Swissinfo, 21 April 2005. 78 CJD Surveillance Centre. 79 CJD Surveillance Centre. http://www.which.net/campaigns/food/safety/bse_reports/bserep0405.pdf TSS
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