Variant Creutzfeldt-Jakob Disease

Thank you for giving me the opportunity to have this debate, Madam Deputy Speaker, which I have been chasing for a wee while, as I suspect the Minister is aware. I apologise to the Minister that she will be the last man standing this evening—that is not a gender mistake but an old saying. I must declare an interest: I am a very part-time dentist, and this matter faintly touches on that. In fact, dentists have been affected to some degree by the recent rules introduced by the chief dental officer. I should like to do a little scene-setting, to which I expect the Minister to add. Variant Creutzfeldt-Jakob disease is rare at the moment, but it is an incurable, fatal human disease that is caused by protein particles called prions. It causes a spongy degeneration of the brain and ultimately death. As I said, there is no cure. In contrast to the traditional forms of Creutzfeldt-Jakob disease, vCJD seems today to have affected younger patients. Normally, older patients are affected. That at least appears to be the fact with the original causal link with bovine spongiform encephalopathy in cattle. However, that cause seems to have been eradicated, so transmission now is predominantly from individual to individual, through blood transfusions, organs or surgical equipment. It is known that the transmission from human to human through, for example, blood transfusion, is 100 times more efficient than from species to species. Carriers of vCJD frequently spend their whole lives as carriers without developing the disease or even knowing that they are carrying it. Unfortunately, it is currently not possible to detect carriers, many of whom are almost certainly present in the population of regular blood donors and patients who undergo different forms of surgery. Logically, that means that unless extensive preventive measures are combined with detection, the population of carriers must increase, which potentially creates a devastating hidden time bomb of vCJD in the decades ahead. The estimate of the prevalence of individuals incubating vCJD today varies from one in 4,000 to one in 20,000. That comes from the Hilton study, which is based on tests on tonsils and appendix samples. Perhaps it is more disturbing that the UK and Ireland almost certainly have the largest per head of population reservoir of that prion in the world. That explains why UK citizens and even tourists who have visited the UK are not acceptable as blood donors in many countries. It is thought that the incubation period of vCJD is decades. Indeed, if it is like kuru, a similar disease found in Papua New Guinea, it could have an incubation period of up to 40 years from the time of exposure to onset of symptoms. Regardless of the prevalence, it is almost certain that this country will have a considerable number of cases in years to come. To make matters worse, because vCJD is so difficult to detect, it is fairly certain that the Hilton study was not 100 per cent. accurate or effective in detecting incubating cases. Having very briefly and in simplistic terms set the scene, it is important now to turn to what the Government can and should be doing to combat this potential disaster which will hit our children and grandchildren. Obviously, it would be absolutely fantastic if a cure could be developed tomorrow and an early step made towards a detection method. I hope that Government funding is being made available for that. However, I suspect that we are a long way off from either a cure or a detection method, and prevention of transmission is the utmost priority. Indeed, it is the only thing that we can do at the moment. With the removal of mad cow disease, transmission now is from individual to individual via blood. The Government have a blood safety advisory body called the Advisory Committee on Safety of Blood, Tissues and Organs, or SaBTO for short. In 1998, leucodepletion was introduced by the UK blood service as a first step in reducing variant CJD infectivity. That process filters blood destined for blood transfusion and removes white blood cells. It was a very useful first step, but at best it only provided a 40 to 70 per cent. reduction in infectivity of donated blood. In July 2009, SaBTO recommended that UK-sourced blood plasma should not be used for transfusion and should be replaced with plasma sourced from other countries with a much lower risk of variant CJD. However, in October the committee recommended the use of a recently developed prion filtration system. That has been produced by Macro-Pharma, a medical device technology company. The filter is called a P-Capt filter and has been designed specifically to work directly with the existing technologies used by the UK blood service. It has been CE marked since 2006, some four years ago. This means that it has passed EU safety and efficacy testing, as required for it to be legally used in the United Kingdom. The filter has been under review by the predecessor committee to SaBTO since 2004 and also by SaBTO since its formation in January 2008. In October 2009, SaBTO recommended several changes. First, it accepted that there was a recognition that further measures to protect the UK blood supply and prevent the spread of variant CJD through blood transfusions should be introduced. Secondly, it said that there was "now sufficient evidence" that the P-Capt prion reduction filter "reduces infectivity" and successfully cleans blood to remove the infective prions that carry variant CJD. Next and most significantly, the committee recommended that the P-Capt filter should be introduced for filtering the red cells that will be given as blood transfusions to those born since 1 January 1996, with the rider that that should be subject to the completion of the PRISM—platelet receptor inhibition for ischemic syndrome management—trials. The fourth recommendation was that the requirement for prion filtration should be reviewed in the event that further data on variant CJD prevalence or filter efficacy became available. Although I recognise that the logistics and finance need to be fully assessed, to my mind this is an absolute must and requires considerable urgency. Personally, I see it as a first step towards filtering all blood from all donors. There is absolutely no reason why these initial steps should not be implemented immediately and the PRISM trial continued alongside. Hand in hand with this approach, the Department of Health has introduced other measures in other areas, and I give it credit for doing so. The other logical means of transmitting the prion is surgery, especially with re-used stainless steel equipment, even if it is sterilised. This concern arises from the fact that the prion is extremely difficult to remove from stainless steel and can often survive standard autoclave sterilisation. Even so, when I discussed this with Professor Pennington, who is an expert on the subject, in October 2007, he pointed out that there was no evidence at that time of iatrogenic transmission. That, I suspect, is down to the fact that it is extremely difficult to find the prion and to get any evidence, certainly in the short term. Motion lapsed (Standing Order No. 9(3)). Motion made, and Question proposed, That this House do now adjourn.—(Lyn Brown.)