BSE Inquiry: The Report, Executive Summary, Key Conclusions

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BSE Inquiry: The Report, Executive Summary, Key Conclusions

Britain Investigates Mad Cow Disease and Variant Creutzfeldt-Jakob Disease

Government document

By: Committee of the BSE Inquiry

Date: 2000

Source: Committee of the BSE Inquiry. Return to an Order of the Honourable the House of Commons dated October 2000 for the Report, Evidence and Supporting Papers of the Inquiry into the Emergence and Identification of Bovine Spongiform Encephalopathy (BSE) and Variant Creutzfeldt-Jakob Disease (vCJD) and the Action Taken in Response to it up to 20 March 1996. London: Minister of Agriculture, Fisheries, and Food, 2000.

About the Author: The Committee of the BSE (commonly known as mad cow disease) Inquiry consisted of a judge, Lord Phillips of Worth Matravers, assisted by June Bridgeman, an expert in public administration, and pathologist Professor Malcolm Ferguson-Smith. The inquiry was announced in 1997 and began work the following year.

INTRODUCTION

Creutzfeldt-Jakob disease (CJD) is one of a rare group of fatal diseases known as the transmissible spongiform encephalopathies (TSEs). TSEs affect the brains of both humans and other animals, such as sheep and cattle. These diseases cause progressive loss of brain tissue, leading to a typical spongy appearance that is evident on post-mortem examination of the brain. CJD causes dementia and a range of neurological symptoms, including unsteadiness and jerky movements. It has always been present in humans and scientists have identified four different forms of the disease. Sporadic CJD primarily affects individuals over fifty and is of unknown cause. Familial CJD is inherited, and is characterized by a younger age of onset and a longer disease course than sporadic CJD. Iatrogenic (acquired through medical treatment) CJD occurs through contamination of the brain and nervous system with infected tissue via medical procedures, such as treatment with human growth hormone.

Finally, variant CJD (vCJD) is the form of the disease that emerged in Britain in the mid-1990s. It affects mainly younger people and has a longer course than other forms—an average of fourteen months between onset of symptoms and death. Early symptoms are often psychiatric, such as anxiety and depression, and there may be persistent pain, with odd sensations in the face and limbs. These are followed by more obvious neurological symptoms and progressive dementia.

The vCJD outbreak in Britain echoed the emergence in the 1950s of a strange and invariably fatal condition called kuru (meaning "trembling with fear") among the Fore people of New Guinea. After years of living among the group, American doctor Carlton Gajdusek (1923–)—who went on to win the Nobel Prize for Medicine or Physiology in 1976—came to the conclusion that the disease was transmitted in the ritualistic eating of the brains of the deceased, a Fore funeral custom. He suspected that one of these brains, at least, must have belonged to someone with sporadic or familial CJD. There were some striking parallels between the emergence of vCJD and its links with the earlier epidemic bovine spongiform encephalopathy (BSE or mad cow disease), a TSE found in cattle. The latter prompted a public enquiry to investigate the cause of the outbreak and the main issues addressed are summarized in the excerpt below.

PRIMARY SOURCE

1. INTRODUCTION

1. In December 1986 a new animal disease was discovered by the State Veterinary Service. It quickly became known as Bovine Spongiform Encephalopathy or BSE. It caused irreversible 'spongy' changes to the brains of cattle and was invariably fatal. The public called it 'mad cow disease.'

2. For ten years the Government told the people:

there is no evidence that BSE can be transmitted to humans;
it is most unlikely that BSE poses any risk to humans; and
it is safe to eat beef.

3. Then, on 20 March 1996, Mr Stephen Dorrell, the Secretary of State for Health, stood up in Parliament and announced that ten young people had contracted a new variant of the harrowing, and invariably fatal, Creutzfeldt-Jakob disease—vCJD—and that it was probable that they had caught BSE. Further cases of vCJD were to follow. By September 2000 there had been over 80 cases and the frequency with which they were being reported seemed to be growing.

4. For nearly three years we have been examining all that is known about the history of BSE and vCJD and looking at how these diseases were handled by the Government and by others in the period between December 1986 and 20 March 1996. This Report sets out what we have found.

5. In 1986 the United Kingdom had a worldwide reputation for competence and efficiency in animal health and welfare matters, and in the handling of outbreaks of serious animal diseases. Its skilled veterinarians and scientists, with the State Veterinary Service and veterinary laboratories in the forefront, operated established processes to identify, contain and eradicate animal diseases. They worked closely with farmers, veterinarians in private practice, public health professionals and the relevant industrial sectors. They raised awareness, gave advice, and recommended statutory regulation where appropriate and compensation if need be. The process required well-established communication between advisers and practitioners, effective systems of animal surveillance and information-gathering, programmes of research, and detailed shared understanding of the links between animal and human health in all its aspects, including the food chain.

6. The UK also had highly regarded public health processes of long standing to handle outbreaks of human disease. These included surveillance, preventive action, such as immunisation and advice, and treatment. The health of the nation was at the heart of the remit of the Health Ministers and the professional responsibility of the four Chief Medical Officers, one for each part of the UK, who advised the Government.

7. What went wrong after the new fatal degenerative brain disease of cattle, BSE, emerged in 1986? Why did the announcement in 1996 that humans had probably been struck down by this particular brain disease find the guardians of public health and the world at large so shocked, and apparently unprepared, and leave the public so disillusioned? Our remit does not extend to the frantic diplomatic activity and other events after that date, but the consequences are still bearing heavily on the British economy and have inflicted tragedy on some families and left blighting uncertainty and fear hanging over many more.

8. The full extent and effects of the human disease will not be discernible for many years to come. Baffling questions include the unusual nature of Transmissible Spongiform Encephalopathies (TSEs), the reasons why specific people have become prey to the human version of BSE, and the extent to which others, particularly those exposed to the agent in the 1980s, may yet develop it. These difficult and still unresolved questions have hampered and bedevilled the whole course of events. What we do know is that as of September 2000, shortly before publication of this Report, over 80 victims of vCJD, most of them young, had had their lives destroyed and their families' happiness and hopes had been irreparably damaged.

9. BSE has been a peculiarly British disaster. Almost all the victims of vCJD have been in the United Kingdom. Only four other human victims of vCJD have been diagnosed elsewhere. Over 170,000 cattle have been diagnosed with BSE here compared with fewer than 1,500 abroad, mostly it would appear traceable to British-sourced animals or infected feed at the beginning of the British epidemic. So far, over 4.7 million British cattle have had to be slaughtered, and their carcasses burned or buried as potentially dangerous waste. A thriving high-quality cattle and meat export industry has been wiped out. The livelihood of thousands of farmers and businesses has been damaged. Even at this tail-end of the animal epidemic there were still over 2,000 cases of BSE notified in 1999 and cases continue to be reported as we write.

10. Small wonder that people want to know why it happened and whether it was handled wisely and well. In particular:

What was the cause of BSE emerging and spreading country-wide? Was it as a result of intensive modern farming practices? Was it a result of inadequate regulation or lowered standards? Why is it so overwhelmingly the UK that has been afflicted?
Seventy-four victims, mostly young people, have died of a new variant of CJD. Is it certain that they contracted this dreadful disease as a result of some form of connection with BSE? If so, why was it that they were struck down?
Was the emergence of BSE and its threat to human health effectively handled by those whose responsibility it was to do so?
Did individuals respond as they should have done, having regard to the state of knowledge at the time?
Was the truth about the nature of BSE and the threat it posed concealed from the public? Has there been a cover-up?
Did we make proper use of our scientists?
Did our health and welfare services adequately cater for the special needs of those who contracted vCJD and their families?
What lessons does the catastrophic course of events hold for public policy and the way we do things in the future?

11. These questions have been very much in our minds throughout this Inquiry, as we have explored exactly what happened day by day during the ten years that led up to the announcement of 20 March 1996 that BSE had probably generated a new and fatal human disease. Some questions, such as the numbers who are likely to succumb to the human disease, we are not in a position to answer. Our remit is to report to Ministers on the course of events and the adequacy of the responses to them in the light of knowledge at the time. We have sought to do so thoroughly and fairly. We have reviewed not only the years since BSE first emerged, but the events that led up to it. We have read a large number of scientific publications. We have sifted 3,000 files of documents, and have studied 1,200 statements and many contributions from the public, whom we have sought to keep fully up to date with every stage of our proceedings. We have listened to 138 days of public oral evidence from 333 witnesses.

SIGNIFICANCE

The BSE Inquiry was comprehensive, thorough, and open (proceedings being updated daily on the Internet). It was complex in that it dealt with an interaction between agricultural, veterinary, and medical practice, as well as government policy. Scientists assume that TSEs are caused by an entity known as a prion, which is a corrupted form of a normal brain protein. The diseases are less well understood than infections caused by bacteria or viruses, which made analysis of the science behind the BSE and vCJD epidemics especially challenging.

The picture that emerged from the inquiry was, briefly, that vCJD is, indeed, the human form of BSE (mad cow disease). The inquiry concluded that infected material—either from sheep infected with scrapie (a sheep TSE) or from BSE-infected cattle—was incorporated into cattle feed. Further, it was found that changes in the processing of carcasses used for animal feed were the likely cause of this contamination. Products, such as burgers and pies, made from so-called mechanically rendered meat (MRM) were contaminated with BSE because MRM typically will contain traces of nervous system tissue such as brain or spinal cord. People consuming these MRM-containing products had then become infected with vCJD. Fortunately, the epidemic, though tragic for the victims and their families, was limited by steps such as the wholesale slaughtering of infected cattle and a ban on imports of British beef.

The inquiry led to a variety of developments. For example, in an attempt to restore public confidence, a Food Standards Agency was set up in the United Kingdom to advise on food safety issues. Regulatory authorities are moving towards eliminating animal products from the manufacture of medicines and other items destined for human consumption. The BSE Inquiry also led to changes in the supply of blood and blood products, in an attempt to screen out donors that are, unknowingly, carrying vCJD. Typically, TSEs have a long incubation time—in the case of kuru, up to forty years. As a result, it is not clear whether more cases of vCJD will emerge. The BSE episode highlighted the problem of zoonotic disease—that is, the transmission of disease from animals to humans. The recent outbreak of "bird flu" suggests that this is a continuing concern, and the lessons learned from the BSE Inquiry will not be forgotten.