Crohn's Disease

HL Deb 19 June 2000 vol 614 cc82-97

7.42 p.m.

Lord Greenway

rose to ask Her Majesty's Government what measures they are taking to prevent the spread of Crohn's disease.

The noble Lord said: My Lords, I ask this Question with some trepidation having no medical knowledge and being only too aware that among those who are due to speak are one or two noble Lords whose experience is considerable, specifically in the field of gut problems.

My reason for asking the Question arises from the fact that my wife suffers from Crohn's disease. For the benefit of those noble Lords who may not have heard of it, Crohn's is a most anti-social and debilitating disease. It consists of severe inflammation of the small and large intestines but in extreme cases can affect any part of the digestive system from mouth to anus. This inflammation narrows the digestive tract and results in excruciating pain during the digestion process as well as constant uncontrollable bowel movements. Added discomforts associated with Crohn's disease include severe joint pains, weight loss and lack of energy.

My wife is more fortunate than most in that she contracted the disease comparatively late in life—some 10 years ago—but today there is evidence that more and more young people, especially those in their early 20s, are being infected. In chronic cases, Crohn's makes it well nigh impossible to lead a normal life. Both work and relationships are put under severe strain. It is particularly distressing to young ladies on account of the disease's most unfeminine symptoms. In severe cases, Crohn's can affect a woman's ability to have children.

The effectiveness of treatment methods remains controversial. They consist of a variety of drugs, including steroids and antibiotics, coupled with dietary changes, all aimed at reducing the inflammation. In severe cases surgery may be necessary to remove sections of the infected intestine or bowel. While that may provide temporary alleviation, it does not act as a cure and the disease can return. In extreme cases the whole colon may be removed.

There is still no recognised cure for Crohn's disease. Although much work has been done, generally it has been hampered by a shortage of funds. The best that a patient can hope for is to be placed in remission which permits him or her to lead a reasonably normal life. However, flare-ups can occur without warning at any time. Unfortunately, some treatments, especially steroids, can also cause unpleasant side effects.

We do not know exactly how many people in Britain struggle through life with Crohn's disease. The best estimates range from 35,000 to 75,000, with between 4,000 and 8,000 new cases being added every year. These are substantial numbers—greater, I believe, than for Aids or TB. Taken with the annual cost of the treatment of Crohn's, averaging about £2,500 per patient, it is not difficult to see that the disease places a considerable financial burden on the National Health Service.

I referred earlier to the lack of any recognised cure for Crohn's, but the valuable work done over the past 20 years by John Hermon-Taylor, professor of surgery at St George's Hospital Medical School, has led him to believe that he has identified the cause of the disease: a bacterial infection known as Mycobacterium avium subspecies paratuberculosis, or MAP for short. Present knowledge suggests that it is responsible for at least 60 per cent of Crohn's in humans, but hunch inclines him to the belief that the figure is even higher. MAP normally infects the intestines of cattle, leading to an incurable and fatal wasting disease known as Bovine Johne's disease or BJD. I referred earlier to my wife's suffering. It is perhaps significant that she was brought up on a dairy farm where the herd was infected with BJD and the family regularly drank raw milk, which suggests that the disease lay dormant until triggered by something later in life.

BJD in cattle is on the increase both in Europe and America, with some 55 per cent of herds at present infected. Infected animals spread the bacteria in their faeces, contaminating the soil and ultimately, through run-off, the water supply. Similarly, there is growing evidence to back Professor Hermon-Taylor's contention that MAP is also secreted into the milk of infected cows and survives the pasteurisation process, which currently involves milk being heated to 72 degrees Celsius for a period of 15 seconds. His own tests on retail milk show that MAP was present in 7 per cent of cartons. The MAP bacteria are difficult to detect and their extremely tough shells makes them difficult to destroy. They can also infect the intestines of many other species of animals, including four types of subhuman primates, with resulting inflammation.

My purpose this evening is to ask the Government what they are doing to prevent the spread of Crohn's disease. I understand that, following Professor Hermon-Taylor's research into milk, they have funded through MAFF an independent research programme to test all types of retail pasteurised and unpasteurised milk. The work is being undertaken by Dr Irene Grant at Queen's University Belfast. Dr Grant is not due to report until November, but I understand that indications from the 802 samples tested to date (by DNA) show that MAP is present in 10 per cent of them and 3 to 5 per cent of the time live MAP can be cultured.

The existence of live MAP in the milk supply is a potentially serious public health problem. I am sure we all agree that the last thing any of us wants to do is to cause another food scare. Besides, milk is a valuable and necessary nutritional supplement for young people. It is slightly ironic that today we have been bombarded with pamphlets urging us to drink more milk. I live on a dairy farm, and I am only too aware of what farmers have had to put up with of late. The last thing I want to do is to cause them further anguish.

However, there are two things the Government can do quickly and quietly which may help the situation.

The first is to make Crohn's a notifiable disease; the second is to compulsorily extend the length of the milk pasteurisation process. I understand that that is being done by a number of retail suppliers on a voluntarily basis. They have extended the time from 15 to 25 seconds. We do not yet know whether 25 seconds is long enough to kill this horrible bug. Further research will need to be done. But it is a useful step in the right direction. Making Crohn's a notifiable disease would be of enormous value to those undertaking research into Crohn's, enabling them properly to assess the remedial effect of their measures. The lengthening of the pasteurisation process, even if it prevented only a couple of hundred young people from being inflicted with this most appalling disease, would in my opinion be well worthwhile. It would also have the added benefit of saving the health service some £0.5 million a year—money which could be well spent on further research into ways of eradicating Crohn's. Additional measures could include the withdrawal from sale of unpasteurised milk and the testing of dairy herds for BJD.

I look forward to hearing the other contributions on this important topic. I hope that the Minister will be able to give some positive answers to my questions.

7.51 p.m.

Lord Turnberg

My Lords, I am most grateful to the noble Lord, Lord Greenway, for his initiative in introducing the debate. I am pleased to have this opportunity to speak. In a previous existence, I was a practising gastroenterologist and spent some 30 years looking after patients with Crohn's disease. I should also express another interest. I am currently chairman of the board of the Public Health Laboratory Service (PHLS) which has some responsibility for testing the microbial safety of food and milk.

As the noble Lord so clearly and movingly described, patients with Crohn's disease may endure much suffering over many years. It is a nasty disease. In the UK the best estimates are that it affects about one in 3,000 of the population. But it is a very mysterious disease. It is extremely variable in the way in which it manifests itself. Some patients have severe disease which causes obstruction, fistulae and the like; and others hardly know they have it. Some patients have severe disease for one period in their lives and then go many years in remission and feel perfectly well. That characteristic makes it extremely difficult to know whether any treatment being given to a patient is effective or whether improvement is simply due to a natural remission which they would have had anyway.

However, the biggest mystery about the disease is that we do not yet know the cause, despite enormous amounts of intensive research. We know something about it. We know, for example, that it tends to run in families; that there is a genetic susceptibility to the disease, but one needs some environmental factor to set it off. That may or may not be an infective agent. The fact that the disease is not more common among spouses—presumably they do not share the same genetic background as their partners—speaks against a simple infection. One does not catch it from being in contact with patients.

Researchers have been looking for years—indeed, since the time of Crohn—for an infective cause. But what infection? All the common ones have been excluded and that has led to a search among the myriad of bacteria and viruses which we normally ingest in vast amounts in most of our foods every day.

Recent attention focused on the measles virus—the attenuated measles virus in the measles, mumps and rubella vaccine—which your Lordships will remember caused such concern a year or two ago when it was suggested that the MMR immunisation was a cause of autism and Crohn's disease. That has almost certainly been shown beyond reasonable doubt to be a false assumption, but meanwhile damage has been done and childhood immunisation rates have fallen. Herein lies the danger of taking an interesting research idea—which it is—and proposing changes in public health policy before the evidence is clear.

What about mycobacterium paratuberculosis? This organism is certainly a reasonable contender and has been so for many years but it is still, to my mind, short of proof. The mere finding of the bacterium in the intestine of some Crohn's patients, and of some other normal individuals, is not proof of causation. Nor is it entirely surprising in view of the fact that the contents of the intestine, at least in the lower bowel, are largely made up of bacteria of various sorts. The fact that some gain access, and several do, into the ulcerated bowel wall from time to time is not unexpected.

The possibility that this organism is a cause of Crohn's disease is clearly an attractive one. There is a considerable amount of circumstantial evidence in favour of it. It is certainly worthy of more research. I know that Professor Hermon-Taylor is actively pursuing this. He and others should be encouraged. But there is a little way to go. We should be cautious in making recommendations in advance of the evidence.

Let me say a few words about the presence of mycobacterium in milk. I should say straight away that the PHLS has expressed a strong view that all milk sold in the UK should be pasteurised. We are regularly reporting small, repeated outbreaks of E.coli 0157, salmonella and campylobacter due to the sale of non-pasteurised milk or cheese. There is no doubt in my mind that the UK should come in line with much of the rest of Europe and bring in mandatory pasteurisation for all milk sold in the UK.

But what about mycobacterium? The noble Lord, Lord Greenway, has quoted evidence that current pasteurisation practices do not necessarily remove all traces of this organism from milk. It is not yet clear whether increasing the time for pasteurisation from the current legal minimum of 15 seconds to 25 seconds will make much difference, although it is a reasonable bet. Indeed, most supermarkets have insisted that the 25 second timing for pasteurisation is used in all the milk they now sell.

I know that the farming community would be delighted to rid their cattle of mycobacteria since they cause illness in their animals. Incidentally, Crohn's disease is not more common among farm workers than the rest of the population. It is an interesting observation. Clearly more research into the best methods of how to clear the cattle and other animals of the organism—it is no easy task— and into better methods of pasteurisation is desperately needed. We await with interest the research at Queen's University, Belfast, at the instigation of MAFF.

Where I believe the danger may lie in precipitate public health recommendations before we have the evidence is in the prospect that the public in general will avoid milk and be tempted to deny their children this important source of calcium and other nutrients on the basis of an unproven link to Crohna's disease. That would be an unfortunate outcome.

7.57 p.m.

Lord Hooson

My Lords, I have always believed that one of the most valuable provisions of your Lordships' House is the Unstarred Question which allows a debate for an hour on a subject such as this. I congratulate the noble Lord, Lord Greenway, on bringing this important subject to the attention of the House and of the public.

I have no qualifications to speak on the subject. My interest has been aroused because I have two relations by marriage who have suffered from Crohn's disease, and I know that it can be distressing and disturbing. It is a matter which should be tackled vigorously by the Government. I wish to ask a few questions on the subject. Perhaps I may say that the two relations by marriage are not related to each other, and that neither was connected in any way with dairy farming. However, I, with a large extended family, was brought up on a farm. We drank untreated milk, as did my numerous cousins. As far as I know, none of my family has ever had Crohn's disease or anything approaching it.

The number of people in this country suffering from Crohn's disease is said to be increasing. Can the Minister confirm that? Is it right that more young people aged between 15 and 25 are known to be suffering from the disease? How many new cases are there annually in this country? Is there any geographical spread? Is the disease more common in some places than in others?

I want to ask particularly about the resources from the Government or other bodies which are attributed to research on the disease. We heard a figure of 60,000 cases in this country and I have even heard mention of 100,000. If that is so—and we know that the disease is so crippling—what resources are given by the Government to research into its causes? What resources and how many hospitals are concerned with research into treatments, following up certain cases? That information is very important. Se often one finds that a great deal of research has been done by one person or one team and that if it had been matched by research done by another team or group of people, the beneficial results could have been brought to maturity much earlier. How much exchange of information is there between the different research teams?

I have seen many documents from the United States on Crohn's disease. Is there co-ordination of research between the United States of America and ourselves? Is the incidence of Crohn's disease higher in this country, for example, than in Scandinavia and other European countries? Surely, there should be an intense interchange of information.

Is anyone in the Department of Health directed to concern themselves with co-ordinating all the information? The disease is so disabling and distressing that it needs urgent attention. I hope that the fact that the noble Lord has raised it tonight will result in a greater sense of urgency in this country.

8.2 p.m.

Viscount Simon

My Lords, while I am delighted that the noble Lord, Lord Greenway, has raised the distressing subject of Crohn's disease, I am slightly confused by his use of the word "spread" because it is not contagious. Perhaps he refers to better and quicker diagnosis. I should like to acknowledge the contribution to my understanding of this disease made by a good friend of mine who suffers from it and who tries whenever possible to lead a normal life.

Repetition in a very specific Unstarred Question such as this is inevitable and I do not apologise for any such repetition which I may make. The thinking is that there are several causes and triggers working together; faulty gene, a slow virus (and measles has been implicated by my noble friend Lord Turnberg) and, as the noble Lord, Lord Greenway, said, something in milk.

Flare-ups can be triggered by increased strain on the system such as a tummy bug, stress, having an accident or other trauma, but sometimes there seems to be no reason at all. I have a nasty problem with my body's immune system, but your Lordships will know that Crohn's is an auto-immune condition where the body attacks itself in what is called an "inflammatory response". Symptoms vary and appear in different sequences and severity for different people with diarrhoea, abdominal pain and fatigue being prominent, but with related symptoms which include joint pains such as arthritis, iritis and skin ulcers.

Apparently, the incidence of the disease is increasing among females in their teens and twenties, but I wonder how much of that is due to better awareness of the condition, which is very hard to diagnose. Following visits to various medical people, my friend's condition was diagnosed after some three years of investigation in the mid-1970s.

Treatment is largely by anti-inflammatory drugs—both steroids and non-steroids—and by drugs which limit the white blood cells. Surgery to remove the affected parts of the gut is also undertaken. There is no cure, just management.

The long-term outlook is for increasing morbidity rather than increased mortality. The body becomes older earlier, bone density reduces as a result of the ingested steroids, there is increased risk of some cancers, and some patients have long periods of remission for no reason. It is necessary for the health service to provide continuous monitoring of patients, plus very close attention during acute attacks, which can last for weeks or months on end.

So what is being done for these patients? I have been told that there is a new drug called Infliximab. This is an antibody given by intravenous infusion for very acute attacks to stop the "inflammatory cascade". But a single treatment involves a 2-hour infusion at a cost of some £2,000 and the side effects or long-term efficacy have yet to be established. I also understand that Chelsea and Westminster hospital have had, or still have, a research project to compare the effectiveness of detecting inflammation between conventional endoscopy, which is intrusive and can need up to 48 hours' preparation and treatment, and the non-intrusive and more pleasant methods of ultrasound and MRI scans.

I wonder what help is being offered to long-term patients as regards nutrition and steroid side effects such as loss of bone density? I would suspect that such help is very hit and miss and at the GP's discretion. And what about alternative therapies? Chinese medicine has, anecdotally, proved effective in reducing symptoms. It is used to help the side effects of chemotherapy patients and cancer treatments, so why not Crohn's? And are there any controlled experiments? The Chinese recommend the avoidance of irritants which produce inflammation, such as pollution, pollen and foods high in histamines, and that seems to make sense. But what attention is being paid to food intolerances as a cause of flare-ups, perhaps exacerbated by a leaky gut which, because of damage over the years, allows substances that should not to pass into the bloodstream? What advice is given to patients? My friend found that eliminating dairy products, alcohol, seafood and tomatoes from her diet has improved her quality of life—a cheap palliative treatment indeed.

8.7 p.m.

Baroness Northover

My Lords, I would like to thank the noble Lord, Lord Greenway, for introducing this debate today and I would also like to express great sympathy to his wife. I feel daunted to be speaking in such stellar company. I am of course following the eminent gastroenterologist, the noble Lord, Lord Turnberg. And I see that I shall be followed by the eminent surgeon, the noble Lord, Lord McColl of Dulwich. I would like to thank Professor Michael Kamm, from St Mark's Hospital, where my husband is a surgeon, for his assistance.

Crohn's disease can have horrific consequences, though thankfully it is rarely fatal. I vividly remember being lent the diary of a patient for whom the complaint was a nightmare; she spent much of her time in the toilet with uncontrollable diarrhoea. Yet she had very active two year-old twins. Children being children, they took advantage of her situation by letting themselves out into the street to play. She felt unable to explain her predicament to her neighbours and they concluded that she was a bad and neglectful mother. As your Lordships can imagine, her sense of self worth was simply destroyed.

It is therefore quite understandable that the noble Lord, Lord Greenway, wishes to prevent the spread of this disease. The Question here implies that this is indeed a spreadable infective condition. However, as the noble Lord, Lord Turnberg, said, we do not yet know its cause. Until we do, we cannot hope to prevent it. Various causes have been suggested for Crohn's disease, including genetic, infective and environmental factors. Even toothpaste has been blamed.

As we have heard, it has been suggested that there is a link with the measles virus. Many parents of young children are very concerned about the possibility that the measles, mumps and rubella (MMR) vaccine is a factor in causing Crohn's disease and autism. I certainly worried about that for my youngest child. The MMR vaccination rate has dropped off. If it drops much further, there is a real risk that measles, mumps and rubella will again become established in the population.

In Ireland, a recent measles outbreak has been linked to a 73 per cent reduction in the take-up of the MMR vaccine. In April it was reported that, among 700 cases of measles in the Dublin area, two babies were fighting for their lives against the disease. In the 19th century, over 5,000 babies out of every million infants died of measles.

Diseases of this nature should not be taken lightly. As we have heard, it is also suggested that Crohn's may be related to an infection such as tuberculosis and passed through cow's milk. The main proponent of this theory, Professor Hermon-Taylor of St George's Hospital, states that, most of Crohn's disease is caused by", this bacterium, and that, Although not all the evidence relevant to this is yet fully published, it is compelling". Nevertheless, it has to be said that his colleagues are not yet convinced.

The Department of Health has promulgated advice on MMR and Crohn's to doctors and to the public. It should now clarify its position on the milk theory and I hope that a statement will be forthcoming. In order to assist such an assessment, it is vital that the health service supports research on this and other diseases. Too often, research is given a very low priority. Only when further research clarifies the causation of Crohn's can we begin to think about prevention.

It is not surprising that public concern exists over such public health issues. Since the 1960s in particular, authority of all kinds has been challenged. The sorry tale that later emerged of knowledge acquired but not shared in the cases of thalidomide and BSE fostered public distrust. Therefore, freedom of information must be at the heart of the NHS and at the heart of government. Only with transparency and openness can trust be developed so that people can make their own, well-informed decisions.

If anything is clear about Crohn's disease, it is that there is no agreed view on its cause and, hence, on its prevention. Where theories which themselves may have damaging public health results are put forward as they have been here, it becomes even more important that there should be transparency and openness. Only then, with all the evidence in the arena, can there be a full and well-informed public debate and perhaps we can move forwards towards the prevention of such terrible cases of Crohn's disease as that of Lady Greenway.

8.13 p.m.

Lord Clement-Jones

My Lords, I add my thanks to the noble Lord, Lord Greenway, for initiating what has been a well-informed debate.

The noble Lord described graphically Crohn's disease and how unpleasant it is. However, it is extraordinary how little information we have about its incidence. We know about the disease but it is not notifiable, and a number of noble Lords have been right to raise the issue of why that is so. It appears that some 30,000 to 40,000 people suffer from the disease. Nowadays, it is estimated that one in 500 people are affected and the incidence appears to have doubled in the past 20 years. Gastro-enterologists with whom I have spoken say that they believe it is now more common than multiple sclerosis and almost as common as Parkinson's disease. Therefore, Crohn's ranks among diseases which are very high in incidence. As my noble friend Lord Hooson stated, we need to be clear about that when we consider the devotion of resources, not only to research but also to treatment.

In recent years, there appears to have been a particular increase in the incidence of the disease among children and young people. As many noble Lords stated, and as the noble Lord, Lord Turnberg, emphasised, the precise causes are unknown. However, it appears to be genetically linked; at least, there is some genetic susceptibility. I do not want to go into great detail on the alleged causes of Crohn's disease, although I believe that the title of the debate is somewhat stacked in that respect. Certainly, at this stage I do not want to comment on the link between MMR and Crohn's because that would draw me into a debate with my noble friend Lady Northover and probably with the noble Lord, Lord Turnberg, as well.

However, the issue of MAP is certainly worthy of comment. It causes Johne's disease in cattle, but the key question is whether a link exists with Crohn's disease. As we heard, Professor Hermon-Taylor, of St George's Hospital, Tooting, examined infected patients and discovered that some have MAP. The research on this matter was first published four years ago and it seems to have resurfaced in the press every year or so since then. However, when one looks back at the press cuttings, it is rather baffling to see the way in which the subject has resurfaced on a regular basis without new research coming forward since that originally carried out in 1996.

As a theory, the link with MAP is strongly contested by people such as Professor Quirke of the University of Leeds. Certainly, the gastro-enterologists with whom I have consulted regard it as a theory which is not proven. They have alluded to studies which show that treatment for MAP by antibiotics has not cured the subjects of Crohn's disease. Therefore, studies have been carried out to test whether treating MAP in Crohn's disease sufferers will cure them of Crohn's disease. However, studies appear to have drawn a negative in that respect.

I understand that the MAFF research commissioned in 1998 failed to show a link with MAP. I hope that the Minister will confirm when the research is due to be concluded and that, as my noble friend Lady Northover rightly insisted, it will be published with full openness. That said, clearly the noble Lord, Lord Greenway, has raised an important issue about the nature of pasteurisation, its effectiveness, whether it is carried out at the correct temperature and for the correct length of time, and so on. Those are all issues to which the noble Lord, Lord Turnberg, alluded in his contribution.

However, generally the debate about MAP raises the major question of why more research is not being conducted into Crohn's by the Government or by the MRC. I pay tribute to the NACC, which raises some £250,000 towards research every year. But why is such a pitiful amount of research being carried out by the Department of Health and the MRC?

In a short debate such as this it is difficult to touch on all the issues relating to sufferers of Crohn's disease. However, issues arise surrounding the new treatments available, alluded to by the noble Viscount, Lord Simon, such as the question of the new drug, infliximab. Each infusion costs well over £1,000 and lasts for approximately 14 weeks. However, I am advised that postcode-prescribing is now applicable to infliximab, as it is to many other important drugs for other conditions. Can the Minister explain when NICE will examine infliximab? Will it be asked to consider whether the drug is an effective treatment for Crohn's disease and make a recommendation to the Department of Health about its availability?

I have a further question. What work is being done on vaccines for Crohn's? Clearly, if only a little research is being carried out, I assume that very little work is being done with regard to vaccines. What kind of training are GPs receiving in how to diagnose Crohn's disease? The diagnosis for young children is particularly important because Crohn's disease can affect their growth. What about the support that should be given to Crohn's disease sufferers? Diabetes is not a particularly well-resourced condition. However, compared to diabetes, Crohn's disease is in an even worse position. There are very few specialist nurse practitioners or doctors. The situation compares unfavourably even with the shortage of diabetes specialists.

Above all, very little advice is available to Crohn's disease sufferers on matters such as diet. There are not nearly enough specialist dieticians or nutritionists available to help Crohn's disease patients. One can only conclude that the research and treatment available for those with Crohn's disease is inadequate. I look forward to the Minister's reply.

8.20 p.m.

Lord McColl of Dulwich

My Lords, I too should like to express my appreciation to the noble Lord, Lord Greenway, for drawing our attention to this important subject and for doing it with such expertise. If he had not told us that he was not a doctor, we might have thought that he was.

The disease affects any part of the alimentary tract. It can also affect other structures outside the alimentary tract. From the specimens, it looks rather like tuberculosis, both in its gross appearance and when it is examined under a microscope. Attempts to culture the tubercle bacillus have rarely succeeded. As has been said, many different etiological agents have been postulated and, as the noble Baroness, Lady Northover, mentioned, even toothpaste was incriminated at one stage.

The possibility of Crohn's disease being due to MAP has been emphasised by Professor Hermon-Taylor. The description "paratuberculosis" suggests that it is like the ordinary TB micro-organism, but in fact it is quite different. It is much more robust. It can survive in the environment and is highly resistant to anti-tuberculous drugs.

Two years ago, Professor Hermon-Taylor described a seven-year-old patient who had had MAP in some of the lymph nodes of his neck. This was followed seven years later by a condition that looked remarkably like Crohn's disease. The patient responded to anti-tuberculous drugs and was advised to have ultra-heat-treated long-life milk because of the possibility that the offending organism was in the milk.

As noble Lords are aware, in the earlier part of the last century, milk was often heavily contaminated with the micro-organism that causes human tuberculosis, which produces tuberculous glands in the neck. Although the organism enters through the mouth, it can affect other parts of the gut. It is postulated that something similar is happening with MAP.

Dairy cows can suffer from the condition, but it is sub-clinical and they go on shedding the offending organism in their milk. Ordinary pasteurisation procedures kill the human variety, but the paratuberculosis organism is much more robust. We must have randomised, controlled clinical trials with anti-tuberculous drugs in patients with Crohn's disease.

As the noble Lord, Lord Turnberg, said, because of the possibility that the disease might be caused by that organism, Sainsbury decided in 1998 to have its milk pasteurised for a longer period. The standard time is 15 seconds at 71.7 degrees centigrade. Sainsbury increased that to 25 seconds just in case. That is a sensible precaution that certainly does no harm. The private sector is to be congratulated on doing that quietly and without any fuss or panic. It was just a sensible precaution.

In a recent paper published this month in the journal Clinical Microbiology and Infections, a research team from the University of Central Florida reports an examination of resected specimens of Crohn's disease. They found the suspect MAP in 86 per cent of cases. They were using a different technique, with an improved liquid culture system and DNA testing of the culture. That is an interesting development. We await confirmation of the work with great interest.

There is no doubt, as has been emphasised throughout the debate, that we need much more research and that we need to keep an open mind.

8.25 p.m.

Lord Burlison

My Lords, this has been an excellent debate. I am afraid that the time allowed has been far too short to do justice to such an important subject. However, I am pleased with the quality of the speakers tonight. The content of their speeches shows that they have the necessary commitment to support those who suffer from Crohn's disease.

I, too, thank the noble Lord, Lord Greenway, for initiating the debate. Crohn's disease is a significant issue for thousands of people and their families, and the effects can be severely debilitating, as the noble Lord said. The noble Lords, Lord Greenway and Lord Hooson, and the noble Viscount, Lord Simon, said that they had friends who suffered from Crohn's disease. My 15 year-old daughter's best friend also suffers from it. I suspect that many people in the Chamber will meet or have as friends people who suffer from this disease.

The prevalence of the disease has increased. As the noble Lord, Lord Hooson, said, during the past few decades, the number of cases has probably doubled. The reasons are not clear. Improved diagnosis may be one factor, but there seems to be a true increase, just as there has been for conditions such as asthma.

The Office for National Statistics estimates that seven people in 10,000 suffer from Crohn's disease. That coincides with estimates from the National Association for Colitis and Crohn's Disease, so it can be assumed that it affects between 35,000 and 40,000 people in this country. I should like to take this opportunity to pay tribute to the NACC and the Crohn's in Childhood Research Association. These charities support Crohn's patients and their families, providing help and advice that otherwise might not be available.

Despite extensive research efforts, the exact cause of Crohn's disease remains obscure. Around the world, clinicians are trying to identify an infective agent or environmental factors that influence the progress of the disease. Viruses, bacteria, refined sugar, high-fibre diets, smoking and even toothpaste, as the noble Baroness, Lady Northover, said, have been vaunted as possible causes. Most of those theories have not been supported by emerging evidence, but we know that smoking is likely to exacerbate the disease and Crohn's is more common among smokers.

In the past 10 years, attention has turned to a possible link with the mycobacterium avium subspecies paratuberculosis—the organism that causes Johne's disease in cattle and other animals. Professor Hermon-Taylor from St. George's hospital and medical school, who has been referred to several times, is a leading proponent of that theory. The Government welcome that contribution but at present, there is no consensus of support for the theory. Experts worldwide are debating the issue and differ in their opinions. Other studies have found no evidence of a link. Indeed, in one study, the only patient with MAP was the one who did not have Crohn's disease. So the link is not proven in scientific terms.

We have taken our own expert advice. The Advisory Committee on Dangerous Pathogens has on two occasions concluded that a link could not be established. A similar view was reached by the EU Scientific Committee on Animal Health and Animal Welfare. It recommended that more research was needed. The Government agree and I shall touch on research in a few moments.

Both water and milk have been suggested as possible routes of human infection and we are conducting studies in both areas. MAFF is conducting a milk survey which will be completed later this year, and the emerging findings suggest that MAP may be present in a small proportion of pasteurised milk on retail sale. If that is confirmed, it is undesirable. In co-operation with the industry and M.AFF, the Food Standards Agency (FSA) will certainly want to consider what steps can be taken to eliminate or reduce the likelihood of that organism being present in milk. Those steps may include the introduction of effective processes known to remove the organism. Different pasteurisation treatments may be investigated further along with hygiene improvements in the milking environment. However, the Government's advice remains that there is no need for people to stop drinking milk or change their dietary habits.

The noble Lord, Lord Greenway, mentioned that water may be a possible source of exposure to MAP. MAP belongs to a group of organisms known as mycobacterium avium complex—MAC—found in natural water supplies. Because these organisms are more resistant to disinfection during water treatment than conventional indicator organisms, such as E. coli, particular attention should be given to them. It is true that strains of MAC have frequently been isolated from natural water sources and from piped water supplies. However, the process used in drinking water treatment, particularly sand filtration and coagulation-sedimentation, appears to be effective in reducing the numbers of any contaminating MAC organisms and MAP is likely to be removed by these processes too.

At the moment, there is no evidence of a causal link between drinking water and Crohn's disease, but methods for monitoring MAP in drinking water were not available until recently. The Drinking Water Inspectorate has commissioned a study into the fate of MAP in drinking water treatment and distribution and an epidemiological study on whether there is a possible relationship between the incidence of Crohn's disease and water sources.

The noble Lord, Lord Greenway, asked about Crohn's disease becoming a notifiable disease. We are not convinced that that would achieve anything which cannot be achieved as well or better by a voluntary approach to collecting information.

Research into the possible causes of Crohn's is also being taken forward by the Medical Research Council. Last year, almost £500,000 was spent in that area and new awards have recently been made. The focus is on the mechanisms underlying the pathogenesis of the disease and how to prevent it. We have also commissioned a £250,000 project through our health technology assessment programme to evaluate the impact of self-management in inflammatory bowel disease.

The pattern of care for Crohn's patients has increasingly been one of change in response to careful clinical appraisal of how the disease affects patients. A range of surgical and non-surgical treatments is now available in primary care and specialist hospital departments. While patients are never cured and many suffer persistent relapses, it is important to emphasise that symptomatic improvement can be achieved for a majority of patients.

The noble Lord, Lord Greenway, mentioned the sale of raw milk. In recent years, the Government have consulted about that and have decided that it is a matter for consumer choice. However, those who drink raw milk are advised that it may contain organisms which are harmful to health.

The noble Lord asked also about pasteurisation times. Currently, there is insufficient information to be certain that extending pasteurisation times will remove the organism from milk. I hope that the results of the current survey will help to resolve that issue.

He referred also to compulsory testing. The diagnosis and control of Johne's disease is complicated and can involve considerable cost. That is due to the long incubation period, difficulties with diagnosis, absence of treatment and persistence of the organisms in the environment. Unfortunately, the tests available at present are not good. Therefore, testing has its limitations.

The noble Lord, Lord Hooson, referred to interchange of research. That is a valid point and I am sure that noble Lords will seek to pursue that. There is regular debate among the scientific community about Crohn's disease at international meetings. The publication of scientific papers results from that.

The noble Lord asked about how much money is being spent. Within the department and the FSA, there are teams which have responsibility for Crohn's disease and for future research in that area. As the noble Lord, Lord Hooson, will appreciate, resources are devoted to that.

My noble friend Lord Simon referred to Chinese medicine and asked whether that helps as regards Crohn's disease. We do not have any evidence from scientific experiments that Chinese medicine is helpful. The Government are always interested in the benefits of traditional medical systems and welcome well-planned research and proposals.

The noble Lord, Lord Clement-Jones, asked about the referral of infliximab to NICE. It has been suggested that infliximab for Crohn's should be referred to the National Institute for Clinical Excellence—NICE. NICE was established in April 1999 to ensure that the National Health Service provides the best possible care with available resources. It gives guidance about the clinical effectiveness and cost-effectiveness of treatment. At present, infliximab does not form part of NICE's work programme. However, a number of possible additional topics for appraisal during the year 2000–01 are currently being considered. I hope that an announcement will be made shortly on that issue.

The noble Lord, Lord Clement-Jones, asked what research is being done on vaccines for Crohn's disease. I do not know of any research at this stage on vaccines which can be developed once an infective cause has been identified. At this stage, we do not know of any infective cause of Crohn's disease.

The noble Lord, Lord Clement-Jones, mentioned the survey in relation to MAP in milk. He asked when the results will be published. A final report detailing the results is expected to be published in 2001.

The causes of Crohn's disease remain unclear. The work we are doing is continuing in a positive direction. We acknowledge that Professor Hermon-Taylor has made an important contribution to the debate, and we welcome that. We are not and cannot be complacent. We are unable to promise people who must live with this disease an instant cure or vaccine. However, we can promise them a commitment to continue to support research and develop treatments to improve their quality of life.

I have not covered all the questions in the time available to me. I shall reply to any questions to which I have not responded in writing to noble Lords after tonight's debate.

Lord McColl of Dulwich

My Lords, before the Minister sits down, perhaps I may seek clarification. I thought I heard him say that Crohn's disease is incurable. It is possible to remove parts of intestine which are infected by Crohn's and the patient may not have any further symptoms. In that sense, I do not think one can say that the disease is always incurable.

Lord Burlison

My Lords, I hope that the noble Lord did not misunderstand me. I am sure that I did not imply that Crohn's disease is incurable. The experience of the noble Lord in this area is such that what he says is much more of a possibility than any mis-explanation I may have given on the issue.

8.41 p.m.

Baroness Amos

My Lords, I beg to move that the House do adjourn during pleasure until 8.45 p.m.

Moved accordingly, and, on Question, Motion agreed to.

[The Sitting was suspended from 8.41 to 8.45 p.m.]