Examination of Witnesses (Questions 320
- 332)
MONDAY 15 OCTOBER 2007
PROFESSOR DOUGLAS
YOUNG AND
PROFESSOR GLYN
HEWINSON
Q320 Mrs Moon: You talked about needing
a magic bullet and we accept there is not going to be a magic
bullet. I think we have moved on. Although I take the Chairman's
point about Edward Jenner, it did work and it was wonderful. Realistically,
given that things mutate, even BCG in humans is facing a challenge
of new strains, do you have in your head a level of efficacy that
actually would mean that you think this is a level that makes
it something we have to do? Is 50% good enough? Is 60% good enough?
Do you have that central figure of efficacy that you would be
looking for as a guideline?
Professor Young: We need to have
some sort of policy. How we are going to use it you would need
to think about before you set that number, what you mean by 50%.
Does that mean 50% of the animals would have no bacteria in them
whatsoever or all of the animals would have 50%?
Q321 Mrs Moon: 50% less episodes
of cattle needing to be destroyed. I was thinking about the long
term. Realistically we are looking at a huge economic cost to
the farming industry. That is what this is all about. This is
not about "Poor badgers, they have TB, we must sort that
out"; this is about a huge impact on our farming industry.
If we can cut TB slaughter of cattle by 50%, would that be good
enough?
Professor Young: That is a policy
question and I think that is what they are working with. Policy
people with Defra are trying to work that through. It has been
silly the way we have had it before that the researchers were
supposed to come up with that view. There has to be a pragmatic
cost-effective policy view that you then feed back into your experimental
design and set the end point.
Q322 Mrs Moon: We also have to know
how efficient you think your product is going to be. If we do
not know that it is effective in at least 60 or 70% of badgers,
we cannot then extrapolate into what the potential impact is going
to be on cattle. Are you going to be able to come up with some
sort of awareness or figure that will let us have some idea of
how effective you think it will be in terms of the overall population
of badgers, bearing in mind that if we are going for a baiting
trial we are going to miss some?
Professor Young: We will come
up with some number. From the under experimental conditions, we
will come up with a hard number from there and it will be something
like 70%.
Professor Hewinson: There are
a couple of things I feel need doing apart from the science and
one is this clear product profile: what do we need, what are we
aiming for. I think you are absolutely right there. The second
thing is a manufacturer and supplier, someone who is going to
hold the licence. Those are absolutely critical.
Q323 Mr Drew: We will not say where;
it is a sore point.
Professor Hewinson: The other
thing I would say in terms of trying to define how effective the
vaccines are, as we talked about earlier, hopefully some of this
field trial will give us some indication of how effective the
vaccine will be in badgers. We have a natural transmission experiment
in cattle where we have infected animals and we introduce vaccinated
and non-vaccinated cattle into that herd of reactor animals to
get some idea of how effective it is.
Q324 Mr Drew: Are we are actually
vaccinating cattle that have been infected by bovine TB who are
suffering at the moment?
Professor Hewinson: No. We are
vaccinating animals and introducing them into contact with infected
animals.
Q325 Mr Drew: There is no point in
vaccinating an animal who already has bovine TB?
Professor Hewinson: No.
Q326 Mr Drew: Is that because of
choice or because you are not allowed to because under the current
arrangements an animal that has bovine TB should be removed?
Professor Hewinson: There is very
little evidence I have seen of therapeutic vaccines. This is one
of the big goals for human vaccine work.
Q327 Mr Drew: Do we vaccinate humans
who have TB?
Professor Hewinson: No, we treat
them with antibiotics.
Q328 Mr Drew: But we then would subsequently
vaccinate them?
Professor Young: No. There is
no evidence that BCG does anything if you have TB.
Q329 Mr Drew: That is why we need
to work on other vaccines.
Professor Young: That is why we
give them very early before you see TB.
Q330 Mr Drew: I thought we still
gave them some BCG. We will take that as the final word. That
was an interesting conclusion. What you have said cannot be unsaid.
We may take subsequent evidence from you. This is an interesting
topic and certainly a topic that has to give us some answers some
time because we cannot go on the way we have been going. I thank
you for your evidence. It is good the Minister has sat all the
way through this session as we will be asking questions of him
subsequently. It has been very helpful and I thank you for being
so succinct because we have kept to just over our hour and we
have some interesting results. Presumably if we wanted to gain
more front-end understanding of how this is working, in the same
way as I saw the presentation on the badger vaccine trial, you
would be very happy to give us something. Could you do the two
side by side? I found the one that took us through how the trials
were actually working very helpful because just listening to you
talking about it is not the same as having someone do a presentation.
Professor Hewinson: It might be
very useful to come and visit us at VLA to see the scope of what
is really required in doing these things. That puts it in context
in a way that really allows you to see in a much better way the
scope of what is involved.
Q331 Mr Drew: I take that as an invitation
that we would be pretty daft not to follow up on.
Professor Young: You can come
and sit in our territory where we would be very much more relaxed.
Q332 Mr Drew: Knowing how time is
limited, could we put the things together and see if we could
do a couple of presentations on cattle, badgers, even if we would
like to cross-mesh them sometime in the future?
Professor Hewinson: Yes. Can I
say one other thing on the time lines? We have put those together
and we feel those are realistic. Those are best case scenarios
if everything goes well but best laid plans of mice and men, and
foot and mouth—
Mr Drew: We are not bringing mice into
this! Cattle and badgers are enough for us.
| 
