Examination of Witness (Questions 100-119)
DR CHRIS
CHEESEMAN
MONDAY 10 FEBRUARY 2003
100. So we have not got something that is tailor-made
as a live vaccine for badgers?
(Dr Cheeseman) No, we have not. I have just been reminded
that there is another problem, and if we have a reservoir of TB
in badgers that is one thing, we could have a reservoir in other
species as well.
Chairman
101. I want to go on to that. Can we just come
back to that and talk about the international things, because
obviously one of the things that is thrown at us is, the Irish
are beginning to get it right, New Zealand have already sorted
it, because they just took the possum out, and when we went there
they did not want to talk about TB, so either they have sorted
it or it is better not to talk to visiting politicians about it.
Now what is happening in different parts of the world, because
there was a call from Jan Rowe to say we should all get together
and get the latest international evidence and we can learn an
awful lot from abroad. Is that true?
(Dr Cheeseman) With respect to New Zealand, they have
a huge problem there, it makes ours pale into insignificance by
comparison.
102. That was why they did not want to talk
to us.
(Dr Cheeseman) And I think they have gone cold on
the idea of vaccines, they have gone back to the old policy of
blitzkrieging possums, and they do this by dropping poisoned carrots
out of aeroplanes, and for non-target species obviously it is
a big problem, and it is not cost-effective unless it is extremely
localised. And that is another thing that perhaps we have not
touched on today, the cost-effectiveness of any policy and who
pays. But anyway the only other place in the world where there
is a reservoir in badgers is Ireland, and the Republic of Ireland
seem to be committed fairly wholeheartedly to the development
of a vaccine. I would say that their constraints, their conditions,
their attitudes are very different from those that prevail here.
It will be interesting to see whether BCG works on badgers, because,
as I say, their trials are underway, but I think they will realise
very quickly that it is not as easy as just finding out whether
BCG works, you have to develop effective delivery systems, you
may have to commit for a long period of time; do you want to do
that, and who is going to pay, these are all huge questions.
Diana Organ
103. When you think of bovine TB in New Zealand,
it is not through the badger, it is through the possum, but Ireland
has got it in the badger; is there anywhere else, other than Ireland
and us, that has got badgers with TB and a bovine TB, the two
together?
(Dr Cheeseman) Anyone else with badgers and TB. As
far as I know, there are records on the continent of Europe, and
bovine TB has been found in badgers in Switzerland, Italy, Spain.
104. They have got cattle?
(Dr Cheeseman) Yes; they do not have a problem, for
some reason, in their cattle, a TB problem. So if there is disease
present in the badgers, as yet, there is no evidence that they
are a wildlife reservoir that is causing infection in cattle.
105. So has anybody studied, say, there is this
badger group, to see whether that whole population is immune?
(Dr Cheeseman) No.
106. Or there is some husbandry, because the
Swiss farmer, for instance, very often, takes their cattle indoors
during the winter and then puts them out on the high pasture in
the summer; is it something to do with their husbandry that is
so different from the way we do it, so they do not have a problem?
(Dr Cheeseman) It may be true. I should say that the
density of badgers in Switzerland is a fraction of what it is
in south-west England, they do not seem at all worried about badgers.
It may be that the husbandry is different as well. So, whatever
it is, the combination of factors that exist in Switzerland is
such that they just do not have a problem, so they are not worried.
But, in fact, the first record of TB in badgers came from Switzerland,
but it was back in the sixties.
Mr Wiggin
107. What about in America?
(Dr Cheeseman) In America, the elk, the bison, the
wood bison, these are all carriers of TB, there is a huge problem
there with wood bison because they are an endangered species,
and there was a veterinary proposal to eradicate one population
because of the TB problem, which did not go down too well.
Chairman
108. Can we just establish, in the UK, because
we have had an international run around the map, what other wildlife
species are known carriers of bovine TB? We have concentrated
on the badger; there are those who would say, and Austin was touching
on this, about what else you could have to take out if you wanted
to eradicate bovine TB if you believed that culling was the answer.
Can we just have a list of what else is in the frame, just so
that he gets his legal brain around this, and also contributing
to the case?
(Dr Cheeseman) The disease can be present in any warm-blooded
mammal species, and so far in this country it has been found in
foxes, we have found it in our current studies in all four species
of deer, that is red, roe, fallow and muntjac deer, for the first
time on record; recently it has been found in stoats, common shrews,
woodmice and squirrels. We have only just gone through the intensive
phase of this work, which is to establish whether M. bovis
is present in any of these species; our next phase of work is
going to be to try to establish the extent of the problem, if
there is a problem, so there will be some extensive sampling of
these species to find out what prevalence there is. And, of course,
whether they constitute a reservoir of TB will depend on a number
of factors, the density of the host, the prevalence of disease,
the pathology that the disease shows in that species, and their
ecology. So, for example, if we find that there is an extensive
reservoir in the common shrew, I doubt very much whether that
poses a threat to cattle; on the other hand, woodmice are found
in dairy buildings, and if we find there is a reservoir in woodmice,
potentially that could be significant. But in the context of vaccination,
if I could just remind you of that, Chairman, if we succeeded
even in eradicating TB in badgers by application of a vaccine
and there was another wildlife reservoir there that could reseed
the infection in the badger population, it would set you back
to square one; and where do you go from there. So I just put in
that point to remind you that there is no quick fix here, it is
a long-term problem and it is extremely complicated, with the
potential involvement of other species as well.
109. Can I ask you about something that we have
received evidence on, and that is trace elements, in particular,
the changing nature of agricultural production, which supposedly
has denuded both stock and, through that, the soil of certain
trace elements, particularly selenium and zinc. Has this got any
merit, this thinking, is it just a contributory factor, or is
it one that is a bit of a red herring?
(Dr Cheeseman) I think it could be, and it is deserving
of investigation, as to whether selenium, for example, could help
the immune system combat such a disease, but I believe that there
are more important factors, like natural immunity to disease in
certain species, the badger included. So whilst these things may
have a role to play, I would not put them high up my list of priorities
for investigation, I think there are more important issues that
we need to know about first.
110. And how do you breed a natural immunity,
in either cattle or badgers, given that we could be culling both,
including those that may develop a natural immunity? There are
those who say this is a disease that we have made a problem, that
in reality if we allowed it to be bred through we may end up with
an answer, but we keep preventing that from happening. Now is
that a viable proposition, or is that just make-believe science?
(Dr Cheeseman) With cattle, you could do it by selective
breeding, and that has been done for many attributes that are
held to be desirable. With badgers, I am afraid you would have
to let nature take its course and allow those populations where
natural resistance is present, if indeed it is present, to develop,
and it may take generations and generations of badgers. We do
have some tantalising evidence from Woodchester that there is
such a thing as natural immunity to TB, these are cubs which react
positively to the ELISA test, which is a test that just looks
for antibodies in the blood. So we know these animals have got
antibodies to TB; for the rest of their lives they are negative
on testing, so they never develop disease, and there is enough
of these animals to make us think that this could be natural immunity.
Now our genetic studies, that I mentioned, if these tell us that
these animals are in some way genetically related, or similar,
that will be another part of the jigsaw and it will tell us whether
this phenomenon does exist. And we are getting there slowly, we
are piecing together this intriguing jigsaw of whether that sort
of phenomenon is important and whether it exists. And then you
have to decide whether it is widespread, and, if it is not present
in all areas where the disease is a problem in cattle, I suppose
you could envisage a policy where you would encourage it, in some
way, but that is way down the road and one which at the moment
I could not really elaborate, other than hypothetically.
111. So it is fair to say that each of the different
proposals, and we have heard, if you like, the two sides fairly
starkly presented, but each of the proposals that those sides
would propose have their limitations and clearly could be counterproductive,
and this is one of the issues to do with bovine TB which makes
it so difficult for us to get a handle on?
(Dr Cheeseman) Yes, I think that is true, Chairman.
I see polarised arguments and I am only interested in a scientific
solution, I think that is the only way out of this problem, it
is extremely complex and it is going to be with us for a long
time to come. I get a sense of déja" vu talking
to you today because I talked to another Select Committee a few
years back and the same sorts of questions were being asked then,
the same questions were asked by Krebs, and before him by Dunnet,
and before him by Lord Zuckerman. Every now and again this problem
causes sufficient angst in the farming and the political community
to want to review it, and each time I say just let us get on with
the research to underpin a proper, one could call it a holistic
approach to the problem. Vaccine may have a role. I believe that
culling may have a partial role, although I would say that culling,
to me, does not look like a sustainable, long-term policy, it
will always come back while the disease remains endemic in badgers;
culling, you have to look at the cost-effectiveness and who is
going to pay. Husbandry is an aspect that we could find will make
a useful contribution to reducing the risks, and I am glad now
that Defra is funding work on the husbandry side. We cannot tell
farmers at the moment that if they do certain things they will
reduce the risks, we can give them commonsense advice, like it
makes sense to keep badgers out of buildings and to prevent badgers
gaining access to cattle feed in fields, but you cannot say to
a farmer, "If you do this you'll reduce your risks by 50%."
We need to get at that so that they can actually quantify what
their biosecurity measures should produce.
112. Can I just ask, there was a husbandry report
which as a Select Committee we did very much encourage, and there
was some resistance. To your knowledge, are farmers taking much
notice of these appeals to improve their husbandry?
(Dr Cheeseman) I have to say, Chairman, that I believe
farmers could do a lot more to help themselves in the biosecurity
of their farm. There are a lot of good farmers out there who do
everything possible; but equally there are some pretty shoddy
operations where there seems to be a complacent attitude, and
I am not sure what we can do about that.
Mr Mitchell
113. Your argument to us is one of despair,
because while we wait for the scientific evidence, gather all
the information, decide not to decide, the problem becomes more
rampant; that is no counsel?
(Dr Cheeseman) I am afraid, Chairman, that is not
my problem. I am as despairing as you are, Sir.
114. But it is this Government's problem, it
is a problem for farmers who are hit by TB and desperately want
something done about it?
(Dr Cheeseman) I can understand that frustration,
but I would say, despite the problems and the delays that the
trial has suffered, we absolutely must see this through, I do
not want us to go back to 20 years ago, when it was just down
to dogma, that would be a very retrograde step. So I would say
be patient, let the research take its course and eventually we
will get a much better scientific—
115. But you cannot put a time limit on it,
you cannot say in 10 years?
(Dr Cheeseman) I cannot make it happen
any quicker, I am afraid, and that is the reality of life, it
just takes time to unravel what is probably one of the most complex
disease problems that there is in the world.
Mr Wiggin
116. I was going to say, what else can we do?
You have seen this before, you know it is not working; what should
Defra be doing?
(Dr Cheeseman) I believe Defra is probably doing all
it can, and I am saying that without any vested interest.
Mr Wiggin: You are the only one, I think, in
the whole world.
Mr Mitchell
117. No-one else has said that to us, I think,
it is not right.
(Dr Cheeseman) I believe that perhaps Defra could
do more if it had more money.
Mr Wiggin
118. If they stopped spending it on badger trials,
they would.
(Dr Cheeseman) Well, they are spending enough to keep
the trial going, but there are other aspects of research that
could be done that are not being funded.
119. Like?
(Dr Cheeseman) I will give you one good example. All
of the badgers that are being killed in the trial, we could be
looking at diet, we could be looking at reproductive biology.
One of the things that is absolutely crucial, if you start to
kill, manage a population, they are going to respond, they are
going to turn up the wick and breed faster. We should be looking
at those carcases to see just what is happening in the proactive
follow-up culls, are they breeding faster; nobody is doing it
because there is not enough money to do it, I think that is lamentable.
Mr Wiggin: Thank you very much.
Chairman: What is left of this Select Committee
are fascinated, we could go on all day. But on that point can
I thank you for giving evidence, in your usual, frank manner.
And, as I said to both the previous participants, if there is
anything that you feel that you would like to have said, and have
not said, please feel free to write to us, but if you have said
it and it is on the record, hard luck, because it will appear
not just on the written record but you might be able to see it
on Sky on Saturday afternoon, if you have got nothing better to
do, which people who watch Sky on Saturday afternoon certainly
have not. Thank you very much.
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