TUESDAY 16 MARCH 1999

MR BRIAN DICKINSON, MR JIM SCUDAMORE, DR CHRIS CHEESEMAN and DR GLYN HEWINSON

  580. I am afraid I misled, it was to be my last question; one of my colleagues has, very helpfully, passed me another to put to you. The veterinary science representatives told us that Woodchester was not a representative site, so badger research was not applicable to other sites?
  (Dr Cheeseman) All I would say is, it is the only site from which we have any data at all. You are quite right that the findings from Woodchester Park are limited, in that they come from one, high density population, but without that information we really would be in the dark. I would be very glad to have similar, comparable information from lots of other replicate study sites, but that has been a constraint of cost.

  581. Gentlemen, you announced a whole flurry of research projects last week, and the cynic might say that was to enable the Minister to have an easier ride when he comes before us later on today, that he managed to announce them before our session began; that would be a very cynical view, I am sure. But they are a very good range of projects, and one of them is a grant of £50,000 to the University of Bristol for a project on the transmission route from badgers to cattle; now that is clearly a very important question. How long do you think it will take to discover what the main route of cross-infection actually is; you have the speculation, how long will it take to establish that?
  (Dr Cheeseman) I do not think that one project will establish the route of transmission, it will certainly help us understand a bit more about the possibilities. There is something known about the route of transmission; we are talking about badger to badger transmission now, are we, or badger to cattle transmission, or both?

  582. Badger to cattle, or cattle to badger?
  (Dr Cheeseman) Badger to cattle; understanding the way in which a small bacterium transmits from one species to another in the wild situation is an extraordinarily difficult thing to do, it has been done in a laboratory, transmission has been demonstrated, that is from badgers to cattle, back in the early years of, I think it was, the late 1970s.

  583. Was that the rather simple experiment with the one badger and one calf in a pen together?
  (Dr Cheeseman) That was the nature of the experiment, yes, and it did demonstrate that eventually the cattle became infected.

  584. Eventually, yes.
  (Dr Cheeseman) But as to the route of transmission, that is much more difficult; we know that most cattle are infected via their respiratory route, and we have a lot of information on the behaviour of infected badgers, and we have surmised on how the organism is being passed, or being disseminated by infected badgers in the field, and we can assume the ways in which cattle might be exposed to that infection. But this is all assumption. It is actually almost impossible, I would say, to demonstrate transmission, to actually track the route of this organism from one animal to another. But it is just a matter of chipping away gradually, trying to understand the circumstances that are important, and all of the variables, such as the weather, that may promote the survival of the organism in the environment; that is going to be important. The husbandry factors on the farm that may predispose the cattle to infection. All of these things together that go to creating a risk to cattle.

  585. So you are not forecasting a breakthrough from any of the research studies you announced last week?
  (Dr Cheeseman) It is not my project, so I should not really forecast anything.

  586. Another one, which earlier witnesses have attached a great deal of importance to, others have rubbished, is the possibility of developing molecular typing techniques, spoligotyping; now there is a research project, I think, some £260,000, involving a bewildering array of agencies, ranging from this country through to New Zealand and The Netherlands, I think, on that matter. Is that going to be an alternative way of establishing, once and for all, that there is a causal link between TB in badgers and TB in cattle?
  (Dr Hewinson) I would say that we have been molecular typing using one technique for the last two years, we have been looking at every isolative M. bovis from cattle and badgers, using a technique that allows rapid fingerprinting, and that does show some very interesting trends, in that one strain of M. bovis seems to be spread throughout the country, whereas other strains of M. bovis based on spoligotyping, this rapid method, cluster in different areas, and you can see those outbreaks clustering in very tight geographical areas. However, I have been involved, in the last two years, in a European Union grant to standardise techniques and to see which are the most sensitive techniques for allowing us to differentiate between strains, and telling us, once and for all, whether those strains are the same or not; and what you have to remember is, just because they are the same with one technique they may not be the same with another, and that raises the whole philosophical question of when do you stop splitting strains. The grant that has been announced carries the people who are world leaders in molecular typing in different techniques, and the idea is to look at situations in Great Britain where we need that epidemiological information and to establish just which techniques are going to give us the best information, to tell us whether the strains are identical. What I would say is, from spoligotyping, in about 95 per cent of the outbreaks the badger and cattle strains match, but, of course, molecular epidemiology on its own will not tell you whether it has gone from badgers to cattle or cattle to badgers; you also need to follow up with epidemiological information, as well. That will tell you whether it is the same strain but not which routes it goes through.

  587. The detailed note of research projects says that this particular project will provide conclusive evidence on whether and to what extent badger to cattle transmission takes place; that is the claim made in the list here, produced by your Department. You seem to be saying something rather different now?
  (Dr Hewinson) I would say that it will tell you that the strains are the same, but you have to take the data in context; what the grant also has is the epidemiological information to do with those outbreaks as well, so that you have to take it in context, not just with the molecular typing but with the epidemiological data as well.

  588. So that claim made in the MAFF document about the purpose of that research project is actually rather overstated?
  (Dr Hewinson) I think, if you read Krebs, that the accumulation of data will give you overwhelming evidence for—

  589. Alright, I will not push the point, because it would be unfair.
  (Mr Dickinson) I think, for all the statements in the document there, there are a lot of wills there, about the potential benefits; they are, to some extent, bound to be aims, I think, and hopes, particularly given the uncertainties of research.

  590. Right; thank you for that. Can I ask just one last question. We have hinted at them already, and Dr Cheeseman mentioned one that intrigues me, which is meteorological conditions; what are the other factors that you think will be floating around out here that we have not thought about that may be important in encouraging the spread of bovine tuberculosis, stress in cattle, increased cattle movements because of the BSE epidemic, are there other things that we should be thinking about?
  (Mr Scudamore) There is a whole list of potential predisposing factors and causes. First of all, is cattle movement, that if animals are infected and they move they have a potential for moving infection. Secondly is other wildlife, as we have mentioned, where the infection is coming from. And whether there are any factors in the animals which are predisposing to infection; and it is well established that stress, deficiencies, can all predispose animals to picking up disease. But the crucial question really is how the mycobacteria was moving from one place to another place, and the intention is to look into all of this with the new epidemiological form that is being devised.

  Chairman: I think that is a very good moment to bring in Mr Todd.

  Mr Todd: Thank you for sending us a copy of this questionnaire, for which—

  Chairman: A draft.

  591. Draft questionnaire, for which many trees must have died to produce it, it is 32 pages long, so it is very much the sort of British and, dare I say, MAFF way of addressing an issue with a large number of questions to ask on paper. Can you explain exactly how it is going to be used; there seems to have been some slight confusion as to whether it is going to be focused on the areas of outbreak and where TB has been shown, or whether there are going to be control processes for it as well?
  (Mr Scudamore) I think I would say that it is a long form because it is a complex problem. The form has a precursor, which was a form that we used in the State Veterinary Service to look into outbreaks; that earlier form was partly as a management tool, that it would enable us to collect the information to deal with outbreaks, and partly as an epidemiological tool, so that we could look into what the cause of the outbreak was, what the origins were, and other factors. And it was accepted, in the Krebs report, that the original report we used was not satisfactory, and, therefore, that one has been developed, it has been trialled, and the intention is to try to find, it is to have three functions. First of all, it is to be a management form, still, that when my staff go to the farm they will be able to look at where the animals have moved, where they need to trace animals, where they need to take action to control disease. Secondly, it is an epidemiological form, where they will get information on the disease, its extent, how many animals are affected and where it has spread. And, thirdly, it is to collect information on the risk factors, which, as the Chairman said, are the management on the farm, the husbandry of the farm, the wildlife on the farm. That form has been developed by committee, to some extent, that it was MAFF—

  592. It does look that way, yes.
  (Mr Scudamore) It was MAFF, it was the Independent Scientific Group, it has been out for consultation, and I think the form we have got now has the majority of questions that we need to have answered.

  593. Have you done a count on the number of variables that might be applied to this form, fully completed?
  (Mr Scudamore) Personally, no, I have not.

  594. Because I wonder how you are going to be able to do effective statistical analysis of this, based on the extraordinary number of possible options that might appear in this, and whether this will produce meaningful data?
  (Mr Scudamore) The form has been developed in consultation with the Independent Scientific Group, and I think that is a very important point, because, in terms of the statistical expertise, that is where the statistical expertise behind that form lies, I will come on to when it is going to be used. But the intention is the form will be filled up and it will be loaded into a computer system, and I believe the access database will allow analysis to be made of the variables, but I am not completely au fait with the database.

  595. I am sure a database can be produced to incorporate all of these points, but the difficulty is, because you have chosen so many different variables, whether significance will be applied to any of the data that comes out of it, because the range will be so vast. I wonder whether some degree of targeting, which indicated the areas of most likely concern, in both husbandry and landscape types, and things of that kind, would have been a more appropriate way of doing this?
  (Mr Scudamore) I think there are actually two issues; the first one is the collection of the data, and the second one is the analysis of the data. With that form, we will collect a wide range of data; in terms of analysing the data, we could, I think, as you suggest, home in on specific areas, and I think that is going to be a very important point. We might want to home in on one area, find it is not significant and move on to another area. I think, on the statistical analysis of that form, it is accepted that some of the risk factors will be very difficult to tease out, and it is going to take quite a long time and quite a lot of outbreaks before we can get the results of the statistical significance of some of the points in the form itself.
  (Mr Dickinson) Could I, just a balance. It seems to me that, when one is doing an exercise of this sort, part of the problem is, when you are building up a database, that you are trying to cover yourself for the future against things you have not yet thought of, which you may not initially want to analyse but which, down the track, may turn out to be significant in a way you have not foreseen. And so what we are trying to do is make sure that we do not come back in five years' time and say we wish we had collected that from the start; so that, even though we may not want to use a part of it, initially, it is as well to have the lot for later on.

  596. Is it not, in a way, the extraordinarily inclusive approach that has been adopted here, effectively, a confession of complete ignorance on this subject; that, really, MAFF do not have any way of determining, at the moment, why this happens, the various linkages, and so on, and that the last, I do not know, 20, 30 years of people being concerned about TB and its passage from badgers has been a waste of time?
  (Mr Scudamore) I do not think that is correct, because, in fact, we have collected information through other systems. This form is a new epidemiological form, it is to try to pick up the items identified by the Krebs report, basically, in consultation with the ISG. Prior to that, we used the form called TB49, where we collected information, and we extracted, off that, information we needed; but it was primarily to control outbreaks, that we used that form, and to identify origins.

  597. So TB49 provided you with no useful information on the epidemiology of the disease?
  (Mr Scudamore) I think it was criticised in the Krebs report because it tended to put the origin of the outbreak at the end of the form, and there were only six origins, and people tended to fill those up. What I think Krebs wanted was a more inclusive form that would cover a range of topics, so that we could start to get the evidence on the husbandry factors and other risk factors.

  598. I am conscious of the time. Can you explain how it is going to be used?
  (Mr Scudamore) Yes. The form has already been piloted on 29 farms; the intention is that it will be used both in the trial areas and outside the trial areas. In the trial areas, it will be used for the incidence, in other words, the herds that have an incident of TB will be used for all of those, and there will be a number of controls, which will have a shortened form, and initially there will be one to one, so for every outbreak in a trial area there will be one control. The intention is to raise that up to three controls, so there will be one farm with an outbreak, three that do not have an outbreak, which will be similar in terms of geography, herd size, and the intention is to be able to compare those. In addition to the trial area, the intention is to use the form on all outbreaks in the whole of GB; in other words, whenever there is an outbreak of disease that form will be used. Because, as I mentioned, it is to be used for management purposes, epidemiology and data collection purposes; so the intention is that it will be used, as soon as it is finally approved, for all outbreaks in GB. We would also want to try to back-date it to 1 January, if we can, so that we have a database for the whole of this year; but, again, that depends on resources, because it is quite a time-consuming form to fill up, and it will be filled up by veterinary officers or Animal Health staff who have been properly trained, with a standard operating procedure to follow, to fill it up.

  599. Contracts have only recently been agreed for analysis of existing data; does the work on this have to await the resolution of that?
  (Mr Scudamore) As I mentioned, we already have a lot of existing data, and I think the contracts will be retrospective, using the TB49 information and postal surveys; so if we have to wait till all that is collected we will wait for a year at least till we have got a database that can be analysed.