Examination of witnesses (Questions 440-459)
WEDNESDAY 25 APRIL 2001
PROFESSOR DAVID
KING, DR
NEIL FERGUSON,
DR ALEX
DONALDSON AND
PROFESSOR MARK
WOOLHOUSE
440. How long can a decision be delayed, on
vaccination?
(Professor King) Our advice was that vaccination was
an option that should be moved on very quickly, when we gave our
advice.
441. Very quickly?
(Professor King) Yes.
442. Would there be any advantage in a voluntary
vaccination scheme?
(Professor King) I can see no advantage at all in
a voluntary vaccination scheme; the uptake is likely to be too
small to make it worthwhile, is it not? Certainly, we spoke to
a large number of farmers who feel very strongly in favour of
vaccination, I know.
443. They have been on the radio; but, from
what you are saying, I get the impression vaccination is now off
the agenda, is that correct?
(Professor King) Vaccination is still being kept as
an option.
Chairman: After that illuminating circular tour,
now then, David Drew.
Mr Drew
444. I am just intrigued at the famous 52 questions,
although I seem to have 51 questions and I know it has been referred
to as 50 questions before, from the NFU. Who has written the response
to those questions; have you been involved in each one of those?
(Professor King) No. I think the questions you are
referring to are the National Farmers' Union questions that were
put to MAFF, and the responses came from MAFF; we had some input
into the responses but, essentially, that is a MAFF document and
not an Office of Science and Technology document.
445. But you are happy with those answers?
(Professor King) Broadly.
446. You have obviously talked to the NFU directly,
as well as talked to MAFF?
(Professor King) I think, broadly, those answers are
basically factual; but you may ask me about specific answers.
Chairman: We will not ask you to identify the
ones that are not.
Mr Drew
447. No, we will not ask you to identify which
ones are not factual. Clearly, you have had this paradox, which
I raised with Nick Brown on Monday, that, in the main, conventional
farmers have argued the case against vaccination, whereas organic
farmers, led by The Soil Association, have argued the case for
vaccination. How would you argue with The Soil Association, on
the basis that they would say, "Let's vaccinate; let's not
just mess around with ring-vaccination, let's vaccinate all animals,
that's by far the most sensible way to take it forward"?
Indeed, Friends of the Earth, reading their material, would probably
argue Government should have vaccinated well before there was
any possibility of an outbreak?
(Professor King) We respect the opinions of different
groups of people. We put forward a view on the limited use of
vaccination, and this is the only area where the science group
felt it could advise on this, and, as Dr Donaldson said, we were
absolutely unanimous, within the science group, on our advice.
Having put that out, there are differing opinions out there. We
are aware of the fact that vaccination raises issues amongst the
public. We have given our best scientific advice.
448. One of the things that I find very confusing
is, you hear all these wonderful stories from elsewhere in the
world; is there a vaccination policy out there which is a model,
where animals are regularly vaccinated and we can see the epidemiological
impact as well as the economic impact and have some evidence that
we can get hold of, rather than apparently what we are trying
to do, which is nail jelly on the ceiling, at the moment?
(Professor King) Chairman, you have sitting in front
of you the person that any country in the world would invite to
advise them on this, and that is Dr Donaldson, so perhaps I should
ask him to reply.
(Dr Donaldson) I can sympathise, because the issue
of vaccination is a complex one, and to get to grips with it requires
an understanding of the different types of vaccine which exist,
the response of different species, which are variable, and then
the different vaccination strategies. But just to give you an
example of where vaccination has been used successfully on a wide
scale, we can look at the nearby continent of Europe. When it
became possible, in the mid 1950s, to produce foot and mouth vaccine
as a product on a mass scale, vaccination was introduced progressively.
At that time, there were hundreds of thousands of outbreaks per
year in Europe, hundreds of thousands. Over a period of about
15 years, mass vaccination, which was applied generally only to
cattle on an annual basis, reduced the incidence down to hundreds
of outbreaks per year, but, nevertheless, there was the continued
occurrence of outbreaks, and that occurred by about the 1970s,
or so. As the amount of infection became reduced, additional policies
were brought in to try to make control more effective, and those
generally consisted, in the event of an outbreak, of stamping
out the infected animals and ring-vaccinating around it. The mass
vaccination continued, that is prophylactic vaccination, year
in, year out. But even with those policies, if I remember correctly,
during the years about 1982 to when vaccination ceased, there
were upwards of 2,000 outbreaks on the continent of Europe. So
when I say that mass vaccination was successful, that is in relative
terms; it brought the incidence of the disease down to a level
where it became possible to bring in additional policies to eradicate
the virus. Vaccination does not eliminate the virus; vaccinated
animals remain susceptible to the virus, they can replicate it,
they can shed it, they can infect other animals. It is only when
you bring in additional policies, such as stamping out, movement
control, disinfection, decontamination, that you are ever going
to eliminate the virus itself. So if we were to apply mass vaccination
in the United Kingdom, without the continuation of stamping out,
I would suggest we would end up with an endemic situation. And
even to bring in mass vaccination in the United Kingdom, as a
means of controlling this epidemic, you would be talking about
vaccinating upwards of 40 million animals per year.
449. Can I contrast what we have done in this
country with what is happening in The Netherlands, and I think
it would be useful to get a scientific appreciation of what is
happening in The Netherlands, because certainly the media led
us to believe that The Netherlands was going along the vaccination
route. I do not think they made it quite clear whether, as you
said, they were going along what aspect of the vaccination route,
and we now hear that, of course, they have got additional problems
in The Netherlands and it was always the intention to cull out
the animals they vaccinated. Can you just give us some comparison
and contrasts, and perhaps Dr Donaldson would like to carry on,
to see what we can learn from these different approaches?
(Dr Donaldson) My understanding, and I have not been
keeping as close an eye on The Netherlands as normally I would
like to but I have been rather preoccupied with what is going
on in this country, is that in The Netherlands they used vaccination
at the beginning to try to dampen down the situation, and they
got the agreement of the European Union to do that; but I understand,
now, that they have also agreed that they will slaughter out the
vaccinated animals. So they may have had some improvement as a
result of it, but, the vaccinated animals, my information this
morning is that those animals will be culled out; so it would
be a very mixed blessing.
(Dr Ferguson) There is a key point about when you
use vaccination to control an epidemic; if you have only one or
two cases, as they do in The Netherlands, you can use vaccination
in that case; it is never as efficient as culling straightaway,
but the total numbers requiring to be vaccinated are not necessarily
that large. In the state we are in at the moment, if we wanted
to use it—and certainly a few weeks ago—and if we
viewed it as an alternative to culling, then the numbers of animals
requiring to be vaccinated to control the epidemic at that stage
would have been truly phenomenal, many more times than we would
actually need to cull to control the epidemic.
(Professor Woolhouse) And, just to add to that, not
just vaccinated but vaccinated quickly, that is the difficulty.
(Dr Ferguson) I think that's one of the things about
the logistic difficulties of vaccination, and maybe the early
information you got sent was about people considering vaccination
as a means of controlling the epidemic in the state we were at
the beginning of April, the end of March, as compared with vaccination
to protect certain groups of animals. And the two situations are
rather different, in terms of their logistical implications, at
least.
450. Can I take up the second of those points;
so is there a case, for example, for the vaccination of rare breeds?
(Professor King) Once again, we were asked to give
advice on that, and our advice was that we could not see a particular
situation for rare breeds where vaccination would be advisable.
For example, if we look at the hefted sheep in Cumbria, the Herdwicks
and the Swaledales, and so on, there is a problem associated with
vaccinating animals and with the way the disease spreads in the
animals; in sheep, the disease can be quite quiescent, as you
have heard, but if sheep are placed under stress the disease can
move quite rapidly to the infectious state.
Mr Mitchell
451. Stress, like transport?
(Professor King) Stress, like transport, stress like
being taken to Longtown market, so you put a lot of sheep together
in Longtown market and they become more susceptible to the disease;
stress, such as taking Herdwick sheep from the fells, herding
them together to vaccinate them, could itself be a cause for spreading
the disease. So our advice, on the basis of this, was that biosecurity
and surveillance was the best way of handling the problem with
those sheep, with the hefted sheep. So the only case where we
were ambivalent, where we were not absolutely clear, was with
zoos, where we felt that in the case of zoos this should be up
to the local manager, but we could not see that there was a threat
posed by zoo animals to spreading the disease outwards, and nor
could we see a threat from outside the zoo into the animals, either
from people visiting the zoo or in other ways. So, in our advice,
we came down with only one route for the use of vaccination.
Dr Turner
452. Just a very quick one, on vaccination.
Given the response I had earlier about the different strains,
does vaccination have to target strains; if, in fact, you saw
yourself trying to protect the country from what is a generic
disease, would you have to have some sort of multi-vaccination
programme?
(Professor King) No, this is the `O' virus and the
fact is that the vaccine that we have stored at the Pirbright
Laboratory is aimed at that particular virus.
453. I am asking the question whether a vaccination
policy, because some people are saying we should have vaccinated,
in fact, before we even got it, what do you vaccinate against,
is the question we are asking?
(Professor King) That is right; it is, in this sense,
I believe, like influenza epidemics, where we get a different
strain coming by every year and so our GPs have to wait until
the last minute to find out what strain is coming before you get
vaccinated. In this case, as Dr Donaldson said, there are seven
different strains known of the foot and mouth virus.
454. So, for example, in Europe then, what did
they vaccinate against? I understood, and that was what I was
slightly confused about, that Dr Donaldson was saying that there
was a vaccination policy for many years in Europe; what were they
vaccinating against?
(Dr Donaldson) They vaccinated against the strains
which they thought presented the greatest risk, it was generally
a trivalent vaccine, so there were three strains in the vaccine
at that time. Vaccination was eventually phased out in Europe
between 1990 and 1991, because they wanted to have a unified policy
across Europe, in anticipation of having the Single Market and
free movement. So the two policies; the possibility of pan-vaccination
across Europe, or no vaccination and the use of slaughter out
was considered in the context of cost/benefit, and they elected
for the non-vaccination policy and the control by stamping out,
with the possibility, as has been used in Holland, of using emergency
vaccination as an adjunct to stamping out. But, to go back to
your question, yes, in this country, if vaccine were used it would
be used with a strain appropriate to the field strain; there would
then be a complication, that the vaccinated animals would be protected
only against that strain, so if vaccinated animals developed disease
you would have to ask the question, have they been infected with
the strain that is now present, or have they been infected with
a new and different strain. So it would complicate the situation
very considerably.
Mr Drew
455. Do we know what the long-term impact of
a vaccination policy is on species; in as much that, clearly,
if we are talking about vaccinating against foot and mouth, to
go on to my other obsession, bovine TB, the long-term solution
is seen to be developing a vaccine? Do we know what we do to animal
species if we keep vaccinating over not just one generation but
continual generations?
(Dr Donaldson) I am not aware that there are any detrimental
aspects to the continued vaccination of animals against foot and
mouth disease. Some of the cattle on the continent of Europe were
vaccinated right throughout their lifetime, up to the age of perhaps
nine, ten years, and without any effects, that I am aware of.
Mr Borrow
456. Ministers have made it clear this week
that there is no method of disposal of carcasses which does not
pose any threat to human health. What advice has your committee
given to Ministers on the relative health dangers of different
methods of disposal, and also the dangers of not disposing of
animal carcasses in the first place?
(Professor King) My response to your question is the
following, that when I was asked to set up a committee, or a group,
I set it up on the basis of looking for experts in foot and mouth
disease, and the experts that are on the committee deal with that
aspect only. The function of the Chief Scientific Adviser, as
I see it, is to set up groups of this kind, on an ad hoc
basis, to deal with crises. I have not seen fit to set up a separate
group, nor, to be honest, have I had even a moment in my day when
I could have done this, to deal with the issues that you have
now raised, which are vital issues. But I am pleased to say that
the Department of Health has handled everything in a very appropriate
manner, and, of course, on CoBRA, I am present and I can give
in my comments on that. There are very significant health issues
that have to be considered, and those health issues are there
whether you bury the animals or whether you burn the animals;
and so, of course, that has been gone into in fine detail. I can
discuss it, but really it has not been my function in this outbreak
to look at those aspects.
457. So the principal advice to Ministers, in
that area, has come through the Department of Health, although
you would be aware of that?
(Professor King) The Department of Health and the
Department of the Environment and the Environment Agency have
all been very actively involved in that.
458. Just touching on an unrelated issue, I
think when we were raising issues with the Minister of Agriculture
on Monday, there was an article in the paper over the weekend
about deer possibly being infected with foot and mouth; at that
time it was not confirmed. I wonder whether, (a) has there been
any confirmation of wildlife infection, and, also, if it was shown
that there was infection within the deer population, would that
have any effect on the modelling that is being done in terms of
projections for the future of the disease?
(Professor King) Right; so there are two questions,
and, the first, I would definitely turn to Dr Donaldson, because
his laboratory has been doing the testing on those deer.
(Dr Donaldson) Yesterday, I reviewed the situation
in terms of what specimens we had received from deer, and they
included some deer which had been killed on roads, others which
had been found dead and others which were sampled as suspect cases.
I do not remember the exact total, but it was somewhere in the
region of 20 or 30 deer which had been sampled; none of them have
been infected with foot and mouth disease, according to our tests.
We have five, I think, specimens which are still under test, and
so they are incomplete. There have been suggestions that the testing
of deer presents some difficulty compared to other species, and
I would like to refute that; there is absolutely no difference
in specimens from a particular species when it comes to either
isolation or identification of the virus. So the situation at
the moment is, we have, I think it is, about five specimens still
pending results, but up till now we have no positive identification
of any cases in deer.
(Professor King) I think it is worth commenting that
there are also similar lesions possible on deer from other infections.
(Dr Donaldson) Yes, that is correct. Deer, of course,
can die for many reasons; foot and mouth, I should say, will kill
young stock, including young deer, and foot and mouth disease
virus will kill a broad range of young of different antelope species
and will affect the adults of a range of antelope species. Impala,
in South Africa, are not uncommonly infected; we have heard reports
of saiga antelope, in Kazakhstan, having foot and mouth disease.
I have been involved with cases in Israel of gazelle affected.
We have done experimental work at Pirbright in the past with all
five species of deer which are found in the United Kingdom, and
they are susceptible. But, I repeat, we have no confirmed cases
at the moment, and five or so are pending.
Mr Todd
459. What are the risks associated with burning
of carcasses for the transmission of the virus, through dispersal
of it through the lifting of the virus into the air?
(Professor King) Could I just respond initially by
saying, this virus is sensitive to temperature and so, unlike
prions, for example, the virus is destroyed at much lower temperatures.
So I do not believe that this is a problem.
(Dr Donaldson) With a number of agencies, we have
been looking at this possibility, and today there will be discussions
with the UK Met. Office and colleagues at Pirbright who are examining
this possibility. We have also received samples taken from the
air near funeral pyres, which we are testing at the moment for
the presence of foot and mouth disease virus. So far, we have
found no evidence of downwind dispersion of foot and mouth disease
virus to cause outbreaks, but it is still under investigation
and we are looking at all the aspects of it. The time that would
worry us would be when a fire is just started, because that would
be the time when there could possibly be the bursting of the vesicles,
or the dissemination of virus from the surface of the animals,
or from milk from infected animals. Thereafter, once the fire
was burning effectively, I would suggest that the risk of dissemination
from a pyre would be very low, if not zero; as Professor King
has said, the temperatures would kill off the virus.
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