After the storm? UK blood safety and the risk of variant Creutzfeldt-Jakob Disease - Science and Technology Committee Contents


5  After the storm?

88. Variant Creutzfeldt-Jakob Disease (vCJD) is not like other infectious diseases. Caused by a mysterious pathogen which we are still only just beginning to understand, vCJD is an invariably fatal disease of sudden onset, which has historically inflicted on its young victims a progressive dementia more often seen in the oldest and sickest members of society. When the first cases began to emerge in the mid-1990s, the tragic images of young vCJD victims worked alongside the existing narrative of 'mad cow disease' to create an unprecedented level of public anxiety, maintained over subsequent years as the number of cases gradually rose.[288]

89. Underlying this anxiety was the suggestion that these deaths were an avoidable and man-made tragedy: that the Government had mishandled the BSE crisis and was therefore to blame for vCJD. Between 1998 and 2000, the Government's role in the crisis came under increasing scrutiny as a result of the BSE inquiry, and it was during this period that the Government took its first major steps to protect the UK blood supply from vCJD. These steps were largely precautionary: in the late 1990s there were no confirmed cases of vCJD having been transmitted via blood transfusion and many scientists thought this unlikely to occur. Nevertheless, costly risk mitigation measures—leucodepletion and the importing of fractionated plasma products—were implemented as part of a "precautionary policy" which sought to "minimise" any potential risk.[289] In 2004, following the report of the first presumed case of transfusion-transmitted vCJD, a second wave of precautionary measures was introduced: the deferral of donors who had themselves previously received a blood transfusion and an extension of the existing imported plasma policy.[290] In the words of one witness:

    The climate that existed round about 2000 to 2005 was one of real concern. The UK blood agencies and the Department of Health were very concerned that there was going to be […] a growth of cases of vCJD by virtue of blood transfusion. There was, I think, a genuine desire to do something about that.[291]

90. Several witnesses told us, however, that this climate of concern, in which the precautionary principle had been at the forefront of Government policy, dissipated in the late 2000s. The initial wave of vCJD appeared to have peaked and cases were down to a handful a year, leading to a gradual diminishing of the sense of panic that had existed a decade earlier. According to Dr Steven Burton, Chief Executive of ProMetic Biosciences, at this time the "spirit of collaboration" which had previously existed between the Government, UK Blood Services and research companies such as his "disappeared", making it more difficult for new risk mitigation technologies to reach the market.[292] Dr Burton stated that his company was now:

    witnessing an environment where, from our perception, road blocks were being placed in the way and things were being stretched and taking longer. As soon as we achieved one hurdle, another one was, all of a sudden, in the way.[293]

Other witnesses argued that the Government's approach to blood safety was, and remained, "a political issue" and that for many years the Government's uptake of risk mitigation technologies had been based not just on their effectiveness, but on "public sentiment and the perceived risk and need to do something".[294] ProMetic went further, stating its belief that the decision made by the Advisory Committee on the Safety of Blood, Tissues and Organs (SaBTO) not to recommend adoption of its prion filtration technology was based not on the scientific evidence, but on "other considerations" such as cost (at a time of economic austerity) and "a widely held belief within parts of the Department of Health that the vCJD emergency has passed and there [was] no need for the implementation of additional blood safety measures".[295]

91. The Minister told us that "successive governments" had applied a precautionary approach to vCJD and that this had been maintained by the current administration.[296] However, now that the initial storm of cases has passed, we too have perceived a change in the Government's attitude to vCJD. During this inquiry, we have amassed considerable evidence to challenge the Government's claim that it maintains the precautionary approach that it has always taken. For example:

·  The Government accepts that some of those who have potentially been exposed to vCJD and are therefore at increased risk of transmitting it may not have been notified of this risk. These people are therefore not in a position to take the precautions recommended to prevent further transmission. To our knowledge, the Government has taken no steps to rectify this situation and has delegated significant responsibility for ongoing surveillance to the UK Haemophilia Centre Doctors' Organisation—a body which has, for many years now, evidently failed to maintain an accurate record of this 'at risk' population. (Paragraphs 75-78).

·  The Government appears unconcerned by the extremely low rate of research participation from this 'at risk' population, citing this as "a cultural issue" and failing to assure us that it is taking any steps to increase consent rates in order to preserve potentially invaluable scientific information. (Paragraphs 79-81).

·  The Government tells us that it is concerned about the risk of prion transmission via surgical instruments, but is "not aware" of evidence suggesting that national guidance intended to reduce this risk is not being followed. (Paragraphs 27-29).

·  The Government has failed to ensure that a technology with the potential to render this guidance redundant—which was itself based on publicly-funded research—is adopted by the NHS. Seven years after DuPont's Rely+On product received its CE mark, neither it, nor any alternative product capable of inactivating prions present on surgical instruments, has yet been introduced. (Paragraphs 31-38).

·  Despite witnesses overwhelmingly considering a vCJD blood test to be the most important prospective vCJD risk reduction measure—and despite the considerable progress made in the development of such a test—the Government has failed to declare its explicit support for this technology. (Paragraphs 51-52). Moreover, it has taken no steps to ensure that the prototype test developed by the MRC Prion Unit receives the support necessary for the next stage of its development: a blood prevalence study which could also provide valuable data on the rate of subclinical vCJD infection in the UK donor pool. (Paragraphs 61-66).

·  Current assumptions about blood infectivity and susceptibility to infection appear to be largely based on an analysis conducted by the Department of Health in 2011, in which it attempted to solve the 'calibration problem' by matching these assumptions to the observed number of vCJD cases. This is despite fears, acknowledged by the national surveillance unit, that there might be under-reporting of the disease, particularly in the elderly, in whom both classical and variant forms of CJD could feasibly be misdiagnosed as others forms of dementia. (Paragraphs 83-87).

·  After a lengthy evaluation, SaBTO has decided not to recommend the adoption of prion filtration: a technology with the potential to significantly reduce the risk of prion transmission. This decision was made following several years of evidence gathering and a detailed cost-effectiveness analysis, neither of which were carried out in advance of the introduction of another prion reduction measure—leucodepletion—in 1999. (Paragraphs 41-46).

92. We would draw particular attention to this final point. The decision to introduce leucodepletion in the 1990s was a genuinely precautionary step much praised by witnesses to this inquiry.[297] However, had leucodepletion been subject to the same requirements in the late 1990s that prion filtration was in the late 2000s, it would not have been recommended. In 1999, there was little evidence that prions could be transmitted via transfusion and none to conclusively demonstrate that leucodepletion would mitigate this risk. Under today's approach, it is therefore likely that leucodepletion would not have been adopted for several years, if at all.

93. We may never know what the impact of such a delay in the adoption of leucodepletion would have been; whether the measure has saved hundreds of lives or wasted millions of pounds. Because now, as in 1999, there remains "a good deal of uncertainty about the risk" of transfusion-transmitted vCJD.[298] However, while the Government was previously prepared to assume the worst and take every precaution to prevent it from happening, its attitude now appears to be one of measured optimism, in which the apparently low incidence of cases is repeatedly used as a "key piece of evidence" to justify an approach which can no longer be described as genuinely precautionary.[299] We consider this change to be deeply regrettable and unjustified by the available evidence.

94. SaBTO's decision not to recommend the adoption of prion filtration, taken alongside the other evidence that we have gathered during this inquiry, in our view signals a change from what was a genuinely precautionary approach to vCJD risk reduction in the late 1990s to a far more relaxed approach today. Much of the uncertainty surrounding prions, their potential modes of transmission and the possible rate of undetected infection and disease remains: recent evidence that subclinical prevalence could be as high as one in 2,000 people would suggest that a precautionary approach is now more warranted than ever.

95. Our fear is that the Government's current attitude is driven less by the available scientific evidence than it is by optimism: a hope that the storm has now passed and that vCJD is no longer the threat to public health that it once was. In the current economic environment, this attitude is not surprising. However, it is not justified. For all we know, the storm may well be ongoing. We conclude this report by recommending that the Government take a more precautionary approach to both vCJD risk mitigation and blood safety more generally, in order to safeguard against future infections. We suggest that it begin by assessing the key risks, known and unknown, that the UK blood supply currently faces and might face in the future, so that it can identify and fill relevant knowledge gaps and support the development of appropriate risk reduction measures and technologies. The Government should initiate this work immediately and we ask that it provide us with an update on its progress well before the dissolution of Parliament.


288   See Washer, P., 'Representations of mad cow disease', Social Science and Medicine, Volume 62, Issue 2, January 2006, pp.457-466. DOI: 10.1016/j.socscimed.2005.06.001. Washer refers specifically to the "descriptions of the physical and mental decline of the young people who succumbed to the disease, juxtaposed mentally as they are with images […] of uncoordinated and frightened cows", which contributed to the public fear of dehumanisation: "of becoming like a maddened (rabid) animal".  Back

289   Spongiform Encephalopathy Advisory Committee (SEAC), SEAC annual report 1997-98, p.10; p.33 Back

290   Advisory Committee on the Safety of Blood, Tissues and Organs (SaBTO), Measures currently in place in the UK to reduce the potential risk of transmitted variant Creutzfeldt-Jakob Disease via blood, December 2013 Back

291   Q124 [Dr Steven Burton] Back

292   Q124 Back

293   Q124 Back

294   Q125 [Mr Nigel Talboys]; Q79 [Dr Steven Burton]. See also Q74 [Dr Alex Raeber and Mr Nigel Talboys] Back

295   BTO53 [ProMetic supplementary] Back

296   Q295 Back

297   It has been argued that other aspects of the Government's response to the BSE crisis were less in line with the precautionary principle. See, for example: European Environment Agency, Late lessons from early warnings: the precautionary principle 1896-2000, Chapter 15, '"Mad cow disease" 1980s-2000: how reassurances undermined precaution, 2001. Back

298   Q241 Back

299   Department of Health, Blood-Borne Transmission of vCJD Re-Examination of Scenarios, September 2011, p.11. See also SaBTO, Prion reduction filters for red cell concentrates, Agenda item 4, 10 December 2012 and Q287 [Jane Ellison MP] Back


 
previous page contents next page


© Parliamentary copyright 2014
Prepared 24 July 2014