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Scrapie - a pretence of knowledge among the scientists, the politicians and the journalists - and informed comment from those who actually work with sheep....This is nowhere near a complete list.The experiments, injecting brains of live sheep with BSE - costing thousands and being done to hundreds of unfortunate animals -seems wholly unethical. Scientists chasing research grants and politicians obsessed with covering their backs in the remote possibility of BSE jumping the species barrier. No one has proved that vCJD is "the human form of BSE" even though we read it over and over again in the press. Sheep shall safely graze....not in this world, it seems.references from http://www.warmwell.com1. The science2. the politicians3. the journalists4. informed comment from sheep owners....
Moredun scientist says BSE in sheep is most unlikelyMarch 19, 2001 Moredun Institute newsletter"In the last edition of More from Moredun we reported that Moredun had been awarded a MAFF grant of just under 1 million to work on TSE in sheep. The money, which has been granted initially over five years, will allow Moredun to study the infectivity of scrapie and BSE in sheep.
Scrapie is a fatal degenerative disease of the brain of adult sheep and, very occasionally, goats. It has been recognised since the 18th Century and has a world-wide distribution. It is caused by a chemically-unidentified, infectious agent with bizarre properties which is transmitted to lambs from infected ewes both pre- and post-natally, but only produces the disease two or more years later.
There had been fears expressed recently that BSE could have crossed over from cattle to infect sheep and cause a scrapie like disease. However, Dr Hugh Reid, head of the Virology Division at Moredun says "There is, in fact, good evidence now to show that this (BSE jumping from cattle to sheep) has not happened. Since the onset of BSE there has been no evidence of a rise in the incidence of Scrapie in sheep at all."
The evidence available indicates that the feeding of meat and bonemeal from ruminants was responsible for transmitting BSE in the cattle population. "Sheep and cattle rations differ greatly in their compositions" continued Dr Reid. "Any compound food offered to sheep would have been lower in protein than cattle rations, and meat and bonemeal would rarely have been used. Cross contamination of rations is also unlikely in that most cattle feeds are toxic to sheep due to the higher copper levels in them."
Another aspect of scrapie research that is now ongoing at Moredun is to characterise the nature of the infectious agent of Scrapie. Although many have accepted the PrP hypothesis there are many aspects of the biology of scrapie, which cannot be reconciled with this concept. Dr Reid with the assistance of Dr A Dickinson (former Director of Neuropathogenesis Unit) has secured funding from private trusts to conduct research that hopes to characterise the agent of scrapie infectivity in purified preparations that do not contain PrP."
We got an earlier heads-up from "The Scotsman" and "The Guardian" reports but both were so journalistically confused that we decided to just let it ride until harder information was released.
Until there is hard evidence that BSE is occurring in UK sheep --- i.e. in privately owned flocks, not just at various research institutes --- I think such reports should be watched with interest but not concern. When I think back to the 1940s when eating sheep brains was not at all unusual in England -- my mother regularly scrambled them with eggs and we had it on toast, and very nice too -- with the potential for human cases and nothing noted until the mid 1990s and then in relation to bovine TSE, I have personal doubts as to any human risks in this area. Certainly none in relation to scrapie. And if sheep can get BSE it may well be negated as a related zoonosis by their very short lives.
In this instance 30,000 sheep were screened with a yield of a possible 24 with both tests positive, assuming that the second test is reliable. This is less than 1 in 1000 sheep whether they are seeing scrapie or BSE. If the scrapie prevalence is 0.33% (as reported here) one would expect all or most of these 24 positives to be scrapie.
Hundreds of thousands of pounds-worth of well-meaning research has gone into trying to prove that BSE does indeed occur naturally in sheep. Even more has been spent on experiments involving the injecting of BSE material into the brains of living animals. Yet no single case of naturally occurring BSE in sheep has been found.
Assuming that BSE was indeed "caused" by the feeding of contaminated MBM, the thinking is that since both cows and sheep consumed the feed, that BSE could have been passing silently through the sheep flocks by maternal transmission ever since, perhaps "masked" by scrapie.
But what the mathematical modellers may be unaware of - as was the case with FMD - are the realities of farm life. Sheep are not cows - and this difference is not confined to their brains. First, dairy cows, poor manipulated creatures of today, are bred to produce enough milk to be able to feed far more than a single calf. In the days of the "contaminated feed" they were consuming between 1 ton and 1½ tons of dairy cake a year. In contrast, the ewe's contracted stomach while lambing naturally once a year needed to receive only about a kilo for a very short period.
If any ewe had succumbed to "BSE" in the days of infected feed, the only way BSE could have been passed on would have been through the survival of a female lamb born at the crucial and short time of infectivity before the sheep's visible illness would have caused it to be slaughtered.
But new lambs have only a 5% chance of surviving early slaughter. Even if - considering the small amount of feed consumed by sheep - a few lambs with undetected disease had survived into this new generation, what would have been the statistical likelihood of those (female) lambs in turn passing on the disease to their own offspring, born in that short critical period. And then, again assuming that a few of those survived from the 95% slaughtered, what chance of THOSE lambs being able to transfer disease to their offspring? Generations of freakish survival would have had to take place for any BSE to be present in the national sheep flock today.
Looked at this way, the practical and realistic way, the chances of BSE being anywhere at all in British sheep are about the same as the chances of lightning striking the members of the same family every year for ten years.
Yet it is just such a "theoretical possibility" that is driving legislation - legislation such as the Animal Health Bill - which is harming the sheep industry and affecting thousands of lives. The new Act will make participation in the National Scrapie Plan compulsory and appears to provide, with its "precautionary principle", a justification for the removal of other rights of ownership.
Meanwhile, the pronouncements of the FSA , raising serious public fears about the safety of lamb, are driving ever deeper the coffin nails of the British sheep industry.
Is it not time that such theoretical science joined forces with some common sense?
Letter to the Committee Chairman from Dr A G Dickinson (R 11)
(2) The search for the BSE strain in the sheep population
Whether or not it should be a very high priority to search for the BSE
strain in British sheep (or even world-wide) depends on the outcome of
work under the previous heading. There have been hints of MAFF
contingency plans to deal with British flocks on a draconian scale
should the BSE strain be found, which heightens the urgency of answering
the underlying question. But, at least, the Phillips Report kills off
over a decade of MAFF propagation of the unsupported claim that the BSE
strain originated on many occasions from scrapie strains being
transferred to cattle in Meat and Bone Meal. (Unfortunately, the Report
backs an origin for BSE that is implausible in the extreme.)
I was responsible for devising the type of strain-typing test needed
for identifying different TSE strains and, with former colleagues at the
Neuropathogenesis Unit (NPU), devised various means of separating
component strains from mixtures. Nowhere else is there any such
experience. It was a cause for amazement, therefore, when I heard that
MAFF was funding attempts to search for particular strains in the UK
sheep population by pooling the brains of sheep in batches, to economise
this search. They will need considerable good luck with any such
approach. I hope that they have run pilot trials with deliberate
mixtures of a dozen known strains, along with the BSE strain, to test
the proposition. At least, the NPU have declined to adopt any such
This brain-pool approach sounds like another MAFF-associated emulation
of the botched CVL design for cattle "maternal transmission"
experiments, which largely wasted several million pounds and many years.
Is it fair comment to recall that in 1986-87, as director of the NPU, I
only had £75,000 for all our TSE research experiments, after paying
salaries and overheads for nearly 40 staff?
(3) The National Scrapie Eradication Plan for GB
The National Sheep Association know of my long-standing concern about
the often unfounded speculations that have been damaging to their
industry during the last decade.
Late last year, I was shown a copy of the glossy MAFF booklet dealing
with the scheme aimed to eradicate scrapie from British sheep by
breeding from rams carrying a particular version of the gene which codes
for the PrP protein. As I had done the pre-molecular groundwork for
this, by 20 years of selecting sheep genetically for some variants of
this gene, I am in a position to understand the potential complications.
Indeed, it was long realised that the notion of a version of the gene
that would "resist" all known (and future) strains of TSEs, may not be
realistic. This was underlined by the fact that in 10 years of searching
for a strain of scrapie agent that could break such a barrier, I had
been lucky enough to find one, with approximately this property.
Furthermore, this finding was not a surprise because the work with
scrapie in mice had taught me to avoid the notion of genetic
"resistance" to TSEs: this complication is fundamental to understanding
of the whole subject and is widely unrecognised, for example on occasion
by leading members of SEAC. The nagging possibility of "carrier-
infections" with TSE agents is one aspect of this complication.
Where the balance of judgement lies in the present context is dealt
with in the response to the MAFF document appended to this letter, which
is signed by four senior animal-disease scientists [not printed]. It
came as a surprise that the booklet was issued as a "Consultation on
proposals for Phase 1—a Ram Genotyping Scheme" when there appeared to
have been several years of active support by MAFF for implementing this
scheme. It seems to have the de facto status of an ongoing programme.
In closing, I must query the implication underlying the stated
objective of your Committee. A subject like BSE is far bigger than any
single department should attempt to handle. A very significant error was
that MAFF was intent on keeping exclusive control, for example, by their
early determination to exclude the Government Chief Scientist.
I consider it entirely inappropriate that any government department or
group of departments (or their agencies) should control research on
basic scientific issues, especially areas so near the frontier of
knowledge. Such direct control should only involve practical and applied
topics in well known areas. The research role of departments should
focus almost entirely on having first-hand, comprehensive information
about "who and where" there is success, but this must be staffed on
criteria very different from present ones. Whitehall norms will need to
be changed radically, where science is involved.
The basic research should be funded so as to ensure its objectivity
and freedom from coercion—the Research Councils, as originally created,
were well conceived to achieve this. Radical changes are needed to avoid
the administrative traps into which MAFF fell headlong, when it allowed
a disease outbreak to turn into a huge epidemic.
25 January 2001
7 There is currently no evidence of naturally occurring BSE in sheep.
7 Scrapie has been present in sheep for many hundreds of years. It seems odd that this historic disease must suddenly be dealt with in this precipitate and unscientific fashion.
7 Selecting for scrapie-resistant genotypes is not necessarily the correct approach to controlling scrapie and certainly cannot be extended to controlling the theoretical risk of BSE in sheep.
7 To allow inspectors the right to forcibly enter premises, on possibly tenuous grounds, to take samples or even slaughter animals and to threaten those sheep keepers who object with imprisonment and fines is taking control measures to excessive levels with clear infringement of animal welfare and personal liberties.
7 It would appear that DEFRA and its Government Ministers has learnt nothing from the 2001 Foot and Mouth epidemic, in which huge numbers of healthy hefted sheep were slaughtered unnecessarily. (Note: DEFRA has agreed figures from the Meat and Livestock Commision that put the number of animals slaughtered during the foot and mouth epidemic in excess of 10 million). Farmers in the North of England say that they were told “You people have got to realize that we do not need your sheep. We can import all the meat we need”. This does, if true, explain to some extent the Government’s perverse approach
7 The contribution of breeds like the Herdwick and Swaledale to the beautiful environment of the Lake District is crucial, most sheep breeds are not hardy enough to prosper on the Lakeland fells, so how does the Government intend to maintain this unique environment if they kill off locally adapted hefted sheep?
7 The Government is incorrect to assert that SI843 is in line with EU regulations. EU regulations currently in force apply to animals with disease, or suspected of having disease, not to animals susceptible to disease. The European Regulations talk about monitoring of animals that are already TSE infected; the SI insists on slaughter of TSE susceptible animals.
7 These comments also apply to other species in which TSE has been reported, for example, cats, as feline spongiform encephalopathy (a feline TSE) has been reported in this species. There is likely to be a conflict of interest between the provisions of the draft Animal Welfare Bill and SI 843.
7 ‘New Labour – New Life for Animals’ (Labour Party manifesto, 1997) rings hollow. By any measure, and to their utter shame, New Labour has comprehensively failed to treat farm livestock - and their owners - with the compassion that should be the norm in a civilised society.
(Margaret Beckett) It will not be really possible to judge that at this moment. As you know, I believe a paper is on the verge of being published, and I think it may now be out for peer review, but obviously we are talking at the early stages of what is the cutting edge of science, and inevitably these things are not easy. The scientists who have conducted work on the scrapie tests are naturally hopeful, but obviously it depends on other people's judgement of the work that they have produced and hope very, very shortly to publish, and it does depend on people's judgement of that, on the quality of the work, and how quickly such a test could be validated.
Recently, the Government almost unbelievably admitted that DEFRA forgot to apply on time for a share of the European Union's 2003 fund for expenditure on efforts to control animal diseases, notably scrapie and BSE. As a result, the United Kingdom ended up as the only member state to get nothing from the fund, and the right hon. Lady has been reduced to pleading with the Commission to accept a late bid. Above all, British agriculture feels betrayed by the gap between Government promise and Government delivery.
EC sets testing criteria for sheep
An extension of the criteria for testing sheep and goats for TSEs has been adopted by the European Commission, stepping up the numbers which must be tested, raising the total for the EU from 164 000 to 560 000 per year..
The new regulations will come into effect on 1 April 2002, and will include a large number of healthy animals and a further number of animals that die on the farm aged over 18 months. The Commission is raising its budget for the costs of purchasing testing kits from €2.9m to over €6.9m.
Tests to be required on healthy and dead-on-farm animals per Member State:
Minimum Annual Sample Size
Minimum Annual Sample Size
Meanwhile France has announced its intention to test 100 000 sheep (60 000 older animals entering the food chain and 40 000 casualty animals excluded from the food chain). It will use BioRad and Prionics test kits.
Editorial: Country Life Jan 11 2002
The gene is unfortunately present in rare breeds, including the Herdwick, whose preservation was so important during the foot-and-mouth crisis. They would be presumably be allowed to die out. It may be that the government calculates that members of the newly formed Northern Short Tailed Sheep Group are few, and that most voters would not know one end of a Herdwick from another. If so, it confirms the impression that the Animal Health Bill bears the worst hallmarks of New Labour: apparently modern and scientific, actually authoritarian and ill thought through. "
|Source: Farmers Weekly||09 December 2002|
By Jonathan Long
ALL flocks with confirmed cases of scrapie will be forced to have sheep destroyed when EU proposals for a community wide scheme to breed sheep resistant to transmissible spongiform encepalopathies (TSEs) are implemented in the UK.
Documents obtained by Farmers Weekly say that after October 2003, when scrapie is confirmed in a flock, producers in member states will have two options.
Option one allows for the destruction of all sheep in a flock except rams of ARR/ARR genotype, ewes carrying at least one ARR allele and no VRQ allele and sheep with at least one ARR allele which are intended solely for slaughter. It will be compulsory for these flocks to enter a breeding programme to develop a scrapie resistant flock.
The second option allows for the destruction of all sheep in a flock. The document also states that no sheep can be kept on the holding for three years after a confirmed case of scrapie.
In addition, when the affected sheep was not bred on the holding, sheep on the holding of origin may be eradicated as well. If this consideration is pursued common grazing land may be treated as one holding, it adds.
EU proposals come at the same time as DEFRA has begun consultations on a similar voluntary scheme for UK flocks which have had scrapie cases since July 1998, says National Sheep Association commercial manager Chris Lloyd.
The new UK scheme, entitled the Scrapie Flocks Scheme, will allow only rams with the most resistant genotype (ARR/ARR) to be used in scheme member flocks. This scheme will help those flocks which have suffered a case of scrapie since 1998 to avoid another case and it is expected to be introduced in April, says a DEFRA spokesman.
While the requirements for females in scheme flocks will not be as stringent as those for rams, the document says all breeding ewes will have to have at least one ARR allele in their genotype and no VRQ alleles.
"Ewes falling outside of these genotypes, apart from those of ARR/VRQ genotype, will be unable to enter the food chain, but will be compensated at the rate of £90 for adult sheep and £50 for lambs," says the spokesman.
Flockmasters will be eligible to receive either compensation of this level for type three and four rams or be given up to £500 to purchase replacement rams, according to DEFRA proposals.
However, Mr Lloyd believes a discrepancy has occurred because type two rams are ineligible for breeding in the Scrapie Flocks Scheme, but producers will be offered neither compensation nor financial assistance to replace them.
With more than 165 flocks recording a case of scrapie every year, according to DEFRA statistics, it is essential that as many flocks as possible are given the opportunity to breed towards scrapie resistance, it says. But how many flocks will actually enter the scheme remains to be seen.
However, with the EU scheme making genotyping compulsory for flocks experiencing a case after Oct 1, flocks which have already seen scrapie would be well advised to sign up to the Scrapie Flocks Scheme, believes Mr Lloyd.
Despite similarities between the two proposals they will not be combined, says the Defra spokesman.
"Due to the retrospective nature of the UK scheme, flocks will not be incorporated into the EU scheme unless they experience a subsequent case of scrapie after the EU scheme is introduced."
Both EU and UK schemes allow for derogations to be applied where a flock has a limited number of ewes of suitable genotypes.
But the EU proposal says it will only allow a two year derogation, while the
Scrapie Flocks Scheme will allow ewes of less resistant genotypes to be retained
for up to four years.
14 April 2003
The scientist who won a Nobel prize for his work on identifying the cause of BSE-like brain diseases has developed a test that will be used by the Government to see if sheep have been infected by "mad cow" disease.
Professor Stanley Prusiner, of the University of California San Francisco, said the test was 100 per cent accurate and could identify animals with BSE long before they showed the first symptoms of disease.
Tissue samples of sheep experimentally infected with BSE are due to arrive at Professor Prusiner's laboratory this week. He will test the material to see if he can distinguish BSE from sheep scrapie, a naturally occurring brain disease which causes the same symptoms as BSE.
If the test works, it will be used to test the brains of thousands of slaughtered sheep to see if BSE has accidentally infected the national flock. If it has, the Food Standards Agency will be forced to introduce draconian health measures to protect consumers.
"This test has been approved for sheep, and we plan to make it available for sheep and there is this question that everybody is very concerned about, is there BSE in sheep?" Professor Prusiner said. "That's a question that has not been answered yet but it will be answered through commercial testing."
The testing will be done by InPro Biotechnology, a company set up by Professor Prusiner, and LGC, formerly the Laboratory of the Government Chemist, in Teddington, south-west London.
Research on BSE in cattle, scrapie in sheep and Creutzfeldt-Jakob disease (CJD) in humans has been seriously hindered by the lack of a test that can identify the earliest stages of infection when there are no outward signs of illness.
Professor Prusiner said the test, called CDI-5, was the first of a "second generation" of tests that will revolutionise the diagnosis and understanding of neurodegenerative diseases caused by rogue changes in the prion protein of the brain. In addition to being used to detect BSE in sheep, the test will be used to ensure that cattle entering the food chain are free of the disease. This will be important if the Food Standards Agency decides to lift the ban on eating cattle over 30 months of age.
Professor Prusiner said the "bioassay" would eventually be developed as a blood test to see if people were incubating vCJD, the variant form of the disease caused by eating BSE-infected meat. "It became clear to me that we needed a better set of tests and in the early 1990s we began to develop this," he said. "The first generation tests are all based on the immunological assays we developed in the mid 1980s."
"The unfortunate thing about all these tests is that they only really reveal the tip of the iceberg." This was because they did not detect the early stage of infection before the onset of symptoms, he said.
"We developed this test and it has some very important features. There are no false negatives [and] there are no false positives... so this gives us increased sensitivity and increased specificity," added Professor Prusiner.
The key to the test's success is that it can distinguish between the two types of the prion protein – the normal and abnormal forms – and is able to quantify how much of each is present.
Phyllida Barstowe is not only an admired novelist and married to the journalist Duff Hart-Davis, but professionally breeds Wiltshire Horn sheep on their Gloucestershire farm. Until recently her flock roamed happily over the meadows round a fine young pure-bred ram. Then, on 1 September, she was visited by the department for the elimination of farming and rural affairs (Defra), to test her sheep under the EU-sponsored 'National Scrapie Plan'.
To understand what happened next, some background is relevant. Defra, it may be remembered, has spent millions of pounds trying to establish a link between scrapie, a brain disease affecting a tiny minority of sheep, and BSE, a brain disease affecting a tiny minority of cattle. They haven't actually found any link (although readers may recall the famous episode when they tested thousands of sheep's brains for two years, only to discover they had been looking at the brains of cows).
The reason for such excitement, of course, is that Defra still believes there may be a link between BSE and vCJD, a brain disease affecting a tiny minority of human beings. So, if they can prove a link between scrapie and BSE, this would be a tremendous breakthrough, because it would show there may be a link between eating sheep and CJD. They also believe that a tiny minority of sheep are genetically susceptible to scrapie. They have therefore taken this as justification, on EU orders, to test pedigree sheep. Any which do not have the 'scrapie-resistant genes', they can then order to be slaughtered or castrated.
Every step of Defra's tortuous logic is in fact based on a hypothesis for which there is no proof. There is no proven link between eating cattle infected with BSE and CJD (indeed this becomes ever more implausible). There is no evidence that any sheep has ever naturally become infected with BSE There is no evidence that scrapie has ever infected humans. Even the theory about scrapie-resistant genes has been rubbished by one of the top independent scientists in the field. Dr. Alan Dickenson. The whole of the EU's scrapie eradication programme thus rests on a card-house of unproven hypotheses.
When Defra tested the brains of 54,000 sheep from abattoirs, they did find 56 infected with scrapie. But no fewer than eight of these also possessed their so-called 'scrapie resistant genotype'. Since this made total nonsense of their theory, they then carried out another test, which luckily came out with the result they were after: i.e. that only 28 of the sheep were infected with scrapie, none of which had the resistant gene. 'At present it is not known if the cause of these findings' said Defra, 'is a flaw in the methodology'. But, flawed methodology or not, the great thing was they still had the excuse they needed to kill any animal they could find without that 'resistant gene'.
All of which brings us back to Mrs Hart-Davis's Wiltshire Horn ram, Of course it turned out to be the one animal in her flock without the resistant gene. So, although it was a perfectly healthy young sheep, off to the slaughterhouse under EU rules it had to go - on the basis of four different hypotheses piled on top of each other, for not one of which there is any proof a genuine scientist could accept. Mrs Hart-Davis was none too pleased.
They are expected to order further laboratory tests but it might be months before any firm conclusions can be drawn about unexplained results in 28 of nearly 30,000 samples. European food safety authority advisers will also be involved.
Three main options are being examined:
· that there was a problem with the testing method;
· that these results confirm the existence of scrapie, a naturally occurring BSE-like sheep disease never known to have endangered humans;
· that, most explosive of all, BSE, already blamed for killing 136 Britons through food, has spread naturally from cows to sheep.
The chairman of the food standards agency, Sir John Krebs, yesterday told his board of directors: "Our advice to consumers remains the same. We are not advising against the consumption of lamb and sheep meat."
The government is reviewing contingency plans for a sheep catastrophe, long recognised as a theoretical risk. These are believed to include changing the way sheep meat is prepared for food, culling infected animals and other possible contacts, and, in the most drastic resort, destroying virtually the whole national flock of 36m animals.
Tests on sheep infected experimentally with BSE in the laboratory suggest the disease infects far more tissue than it does in cattle, thus making removal of tissue potentially dangerous to people eating meat far more difficult.
However, farmers are suspicious of BSE and scrapie research, especially following the collapse two years ago of crucial experiments meant to check sheep brains for evidence of BSE. It emerged that these were far more likely to have been cattle brains wrongly stored and labelled years before.
The European Union has insisted on more testing of sheep for BSE-like diseases, known as transmissible spongiform encephalopathies, or TSEs. As part of this, material from sheep brains collected from abattoirs has been screened by a rapid test which can be completed overnight. However, this Biorad test has only been formally approved by the EU for tests on cattle, not for sheep.
That means quick tests which reveal positives have to be confirmed by more complicated tests, using a different part of the brain, which can take up to three weeks. In these, tissue is stained to show up the abnormal prion protein characteristic of scrapie. The 52 rapid test results which suggests the presence of scrapie or similar disease were double-checked. In 28 of these extra tests there was no sign of any problem at all.
Sir John said: "This is a puzzling result. It could mean one of several things. It could be a problem with the test and not with the sheep. The test may give false positives. It could be scrapie. The Biorad test might be more sensitive at picking up scrapie than the staining method. It could be a different TSE, possibly even BSE, detected by the Biorad test and not by testing.
"These results do not appear to look the same as when sheep have been experimentally infected with BSE. However, scientists do not know what BSE in sheep would look like, were it to be transmitted from sheep to sheep."
Monitoring of thousands of animals has thrown up 26 more unexplained results since the nightmare possibility that BSE had leapt from cattle to sheep was revealed by government officials in September.
At that time 28 results from samples of nearly 30,000 sheep brains tested up to March were troubling experts. But the puzzling results are continuing at roughly the same rate, scientists on the spongiform encephalopathy advisory committee (Seac) were told.
Government and EU scientists are trying to establish whether there is a problem with the testing method, and whether an unknown type of scrapie, a BSE-like disease in sheep which has never been known to be dangerous to man, or the far more lethal BSE is indeed in our flocks. Meanwhile, the Food Standards Agency is not advising against the consumption of lamb or sheep meat.
The unexplained results come from a rapid screening test which should produce results overnight. Indications of a scrapie-like disease have to be confirmed by another test that takes up to three weeks. In total 54 results have now not been confirmed but this might be because the quick test is better at detection.
Work on establishing the tests' reliability might take months, even after issues of commercial confidentiality over their exact components have been settled. But meanwhile scientists want to start feeding and injecting mice and sheep with brain material that provided the puzzling results.
But this could take months or years and still prove inconclusive. It is quite possible that the brain tissue of sheep has changed its "signature" from normal but is not clinically infected with disease and therefore would have no obvious effect on the laboratory animals. Some types of scrapie also do not transmit at all to mice.
Scientists hope they might get an indication of what might be happening from an experiment that is being conducted in Germany, using material from a sheep there that threw up a confusing result.
Chris Bostock, the Seac member heading the investigations, said: "We do not understand the basis for and significance of these samples." The report from his group presented at Seac yesterday said that the hypothesis that the samples represented pre-clinical BSE in sheep could not be ruled out on the available evidence. But the patterns revealed did not resemble those from sheep deliberately given BSE in the laboratory.
The scientists are seriously concerned by the lack of brain material they can use for further tests. This is because abattoirs have to safely dispose of heads of sheep before test results come back. This rule might have to be altered.
Even sheep supposedly resistant to scrapie have shown unexplained results, worrying for contingency planners already trying to get farmers to breed these types. Scientists have suggested that sheep known not to have scrapie should be tested but finding enough of these in Britain would be difficult.
Some sheep have been imported from scrapie-free New Zealand to use in BSE research but far larger numbers would be needed and it is far from certain that the authorities in scrapie-free countries could, or would want to, provide the numbers needed.
'These diseases are real, fundamental scientific mysteries'
Friday, January 23, 2004
By TOM PAULSON
SEATTLE POST-INTELLIGENCER REPORTER
HAMILTON, Mont. -- At the eastern edge of the Bitterroot Mountains, a craggy range of peaks that defines the border between Idaho and Montana, is a lab full of skeptics who don't hold with the majority scientific consensus on mad cow disease.
They are world-class researchers on these kinds of diseases, categorically called "transmissible spongiform encephalopathies" -- or TSEs.
Some of these diseases have been recognized for a long time, but they captured wide public attention only when it appeared -- first in Britain -- that the disease could get passed on to people who eat beef from a cow with this type of brain infection, which eats holes in the brain.
Americans were reminded of this risk recently after the nation's first known case of mad cow disease (technically bovine spongiform encephalopathy, or BSE) was identified just before Christmas in Eastern Washington.
Most of the scientists here at the Rocky Mountain Laboratories, a branch of the National Institutes of Health, accept that this kind of "cross-species" transfer of a TSE can, on rare occasions, take place. They were some of the first to show it, in fact, in experimental animals.
But try to make any other simple statement of fact about mad cow or Creutzfeldt-Jakob disease, CJD, and you will encounter a stubborn refusal to let you move even one step beyond the evidence.
"These diseases are real, fundamental scientific mysteries," said Dr. Byron Caughey, a biochemist searching for drug compounds to combat TSEs. "We don't really know how they work. ... We only know enough to say they're weird."
The diseases are weird because a misshapen protein appears to spread the infection by causing other proteins in the brain to warp as well. Other kinds of infections, by viruses or bacteria, require transfer of genetic material. Proteins don't do that.
And the scientific inquiry is made more complicated by the fact that this infectious protein process has never been successfully demonstrated in the many laboratory attempts to prove it.
Evidence for the infectious protein theory has been indirect, based mostly on the injection of infected brain tissue into laboratory animals watched for later signs of disease.
"All these diseases are diagnosed based on the presence of these abnormal proteins" in the brain, said Dr. Susan Priola, another Rocky Mountain Labs scientist working on developing vaccines against TSEs.
It is still possible, Priola said, that these bad proteins are a product of viral or bacterial infection -- possibly the real cause of mad cow, scrapie or other TSEs. Although it is possible to fight an infectious disease without knowing its ultimate cause, she said, generally it's a good idea to find the primary infectious agent.
"Everybody says no virus or bacteria has ever been found, but really nobody is looking for it anymore," Priola said. "It's difficult to get funding for such a project."
That's partly because taking such a position flies in the face of the common wisdom and the face of a Nobel Prize-winner to boot. Dr. Stanley Prusiner, the Nobel laureate who coined the term "prion" to mean this infectious protein, contends TSEs are the result of bad proteins only. Most scientists appear to agree with Prusiner, that mad cow, scrapie and Creutzfeldt-Jakob are the result only of prions.
But around these parts, mister, them are fightin' words. Or a fighting word, anyway.
"Don't use that word around Bruce or you'll drive him up the wall," advised Dr. Richard Race, referring to the director of TSE research at the Rocky Mountain Lab, Dr. Bruce Chesebro. Race, a veterinary pathologist, recently proved that scrapie, the sheep TSE, could be transferred to mice, then to hamsters, and back to mice.
"That's similar to what we think may have happened with BSE," he said. "Sheep scrapie was passed into cattle to cause BSE and then it was passed back to humans through the cows to become variant CJD."
Whether it's a prion that's transmitting the infection, Race said, or some other unrecognized virus is still unknown. The confusing terminology in this field fraught with uncertainty, he said, is enough to drive even many scientists nuts.
Chesebro, arguably one of the most outspoken skeptics of the "protein-only" hypothesis, said he's willing to accept the term "prion protein" because it refers to the particular protein involved in TSE infections. He helped determine the exact chemical make-up of the protein years ago.
Everyone agrees that these abnormal prion proteins are somehow involved -- whether acting alone or not -- in spreading these TSE infections.
But to use the word "prion" alone, Chesebro said, is to advocate for a belief system rather than referring to a proven fact.
"Most scientists think this question (of causation) has been answered, the problem solved," he said. "We don't think so."
Prusiner, the Nobel winner, has joined those calling for testing nearly all cattle for BSE and has started a commercial venture to sell what he claims are more accurate tests for BSE. But Chesebro and his colleagues say the science hasn't advanced to allow accurate detection of all infections -- partly because, again, we don't really understand what causes the infection.
"A negative test won't always mean a negative cow," he said. Studies done at the Rocky Mountain Labs also have shown there can be highly persistent infections without any clinical signs, he noted.
More testing might be useful to get a rough idea of how much BSE is out there, Chesebro said, but adopting Japan's approach of testing all cattle only provides a false sense of security. He looked exasperated at having to explain this.
The lab's chief of TSE studies is a highly intense man who wears old jackets and likes to tour much of Big Sky country on skis. He recognizes he and his like-minded team are swimming upstream.
But he believes the holes in the standard theory, like the holes in the brains of those cows, should not be ignored.
It's not clear whether BSE is actually a new disease, created by feeding the renderings of scrapie-infected sheep to cows, or whether it is a long-existent disease that had been extremely rare and unrecognized until the beef industry began making cannibals out of cows by feeding these four-footed vegetarians renderings of their brethren.
It's not been proven what causes any of these diseases, if it is truly a protein or a stealthy virus. But it is clearly a disease that involves the accumulation of bad proteins in the brain, similar to other neurodegenerative -- but non-infectious and clinically distinct -- diseases such as Alzheimer's or Parkinson's.
If there's a silver lining to the first case of mad cow in the United States, it's that the episode is likely to stimulate more research into this long-neglected area of science.
And it may be that the skeptical, stubbornly contrarian attitude of these Bitterroot Valley scientists is just what's needed to figure out what's really going on with mad cow disease and how best to prevent or treat it.
In the foreseeable future a test on blood that can sensitively and accurately predict scrapie infection will be available so that flocks can be tested and regardless of genotype be attested scrapie-free. The European policy seems to be the most elegant and the cheapest one whilst awaiting the day when we can test for scrapie infection ante-mortem.
I understand that his research indicates that BSE and MS are both auto immune diseases, and that these diseases have a link to the presence of Acinetobacter and Pseudomonas. His findings regarding BSE are thus in conflict with Prusiner's Nobel prize winning prion theory.
Professor Ebringer's funding from the UK Department of Environment, Food and Rural Affairs (DEFRA) has just been withdrawn, so that the next stage of his research (to investigate whether vCJD patients also exhibit antibodies to Acinetobacter) has been axed. His entire department at Kings College is to close down, shortly, and all the expertise will be lost.
There is a lot in the news recently regarding the "epidemic that never was", and scientists are hastily revising estimates of future cases of vCJD. Surely, scientists should be re-examining the original prion theory, Nobel prize winner or not, especially the claim (which I understand was made by Prusiner) "A million cattle infected with BSE entered the British food chain so almost everyone in the country will have been exposed to the infectious prion proteins that cause variant CJD..."
However, in spite of this DEFRA is funding further research based on the prion theory, and yet blocking Ebringer's funding. (I refer to the TSE research on sheep brains which I believe is being undertaken by Prusiner, the apparent purpose of which is to prove that BSE can be transmitted across the species into sheep under experimental conditions. It is envisaged that a mass slaughter of the UK sheep flock may well result as a result of this "research". I understand that the nature of the research defies immunological principles, and is therefore flawed). The persistence by DEFRA in funding research connected with the prion theory is all the more surprising in view of the recent funding fiasco in the same area, regarding a long term TSE research project supposedly examining sheep brains. In error, cattle brains had been used in the research.
If Professor Ebringer's theory can be confirmed that BSE and MS are autoimmune diseases which are linked to the microbe Acinetobacter, the implications are of huge importance and are far reaching. The following conclusions arise:
1) There will be no CJD epidemic.
2) A cure for vCJD, based on treatment for Acinetobacter, could be set in motion.
3) BSE cannot be passed on by eating infected meat. The meat from BSE cows is safe to eat and has always been safe to eat.
4) The massive cattle cull was unnecessary.
5) The devastating blow dealt to the UK livestock industry, and elsewhere, was unnecessary.
6) The financial outlay for the BSE disaster of £5 billion of taxpayers money could have been spent on other socially more relevant needs.
7) The massive European and wider research programmes on TSEs in sheep, with potentially disastrous implications for the sheep industry in the UK, are flawed and therefore worthless.
8) A possible cure for MS may be found.
9) The extremely costly tonsil screening programme plus associated costs was unnecessary.
9) Reputations will be damaged.
10) It may pave the way to improving the reputation/perception of science/scientists in the eyes of the public, by allowing scientific research to be open to rigorous peer group scrutiny, by showing that alternative views are encouraged rather than suppressed, and most importantly that funding is not linked to producing politically acceptable results.
How can good science/scientists succeed in the face of seemingly insurmountable opposition?
I want to see good science prevail, and I also wish to somehow make a difference for Professor Ebringer and his team. After I wrote to him requesting information, he took the trouble to send me a brief summary of his arguments, plus copies of articles published. I feel that considerable talent is being wasted, and possible cures for devastating diseases being denied the public. I think that his treatment by DEFRA UK makes a mockery of the research funding process, and represents a gross insult to a highly regarded immunologist.
Anne Lambourn (Mrs)
From the start the project was based on assumptions, theories and not on
sound science. The "unexpected results" might as well be due to other
conditions; a test on metal levels in brain, kidney or liver of animals
suspected should be performed to exclude copper deficiency/manganese toxicity.
When it comes to livestock, performance in science is poor. Humans are capable
of flying to the moon but can't deal with conditions known to mankind for ages.
After nearly two decades of BSE research it resembles a declaration of
bankruptcy that the only solution to all problems should be killing.
To sacrifice hundreds of thousands of animals for no good reason at all is a disgrace. Not the fact that the R1 sheep tested positive with some kind of TSE but the fact that scientists pushed by politicians happily create a nightmare scenario at the expense of farmers and animals alike...
Note well the Blackface champion at the Royal Highland Show Edinburgh, according to National Scrapie Pan would be killed as it is not the type of the sheep (type 5) that they want to breed from. It is merely an animal that has proven abilities to survive in its terrain.
Who would say that this was undesirable? "
§ The "National Scrapie Plan". There is still no incontrovertible proof to link scrapie, B.S.E. and new variant C.J.D., despite the best efforts of certain scientists. There are, however, a lot of hypothetical "what ifs" and "maybes". Scrapie itself has been recorded for at least 250 years. The meat and brains of those sheep have been eaten over the same period with no ill effects. But now it is decreed that only sheep of two certain gene types may enter the food chain or be used for breeding. The remainder, no matter how good or how healthy, must be incinerated at the taxpayers' expense. No one can say what perfectly good and useful genes will go up in smoke at the same time. Practical experience from the Netherlands should give us a good idea. Totally unsuitable rams are now being used, simply because they are of the right scrapie resistant gene type but which, for their other attributes, should have been castrated at birth. At a stroke, a hundred years, or more, of careful selective breeding is being thrown away.