Memorandum from Professor John Bourne
CBE MRCVS, Chairman of the Independent Scientific Group on Cattle
TB (P35)
Thank you for informing me of your intention
to hold a further inquiry into badgers and bovine TB. We have,
in the past, found the outcome of your inquiries very helpful
and we are reassured by your continuing interest.
We have not been asked to provide a full formal
paper but the points that we would wish to address are covered
in detail in Defra's submission to your Committee. This letter
is, therefore, primarily to highlight the key issues on which
you may wish to focus when we meet.
Since your last inquiry our 3rd report has been
published which outlined the progress made on the extensive research
programme now in place, which aims to ensure that future policy
options are underpinned by sound science. The report also included
an outline of a range of potential future policy control options
that the research programme was designed to underpin.
Following our 3rd report we have had to address
issues arising from the foot and mouth disease emergency (FMD).
I understand that your Committee has already seen our preliminary
report on the impact of FMD on the research programme that we
submitted to Defra Ministers in March 2002. We are currently drawing
up a further report, now that the effects of the emergency are
clearer, and we have timetabled this to go to Ministers by the
end of March. To the best of our judgement the direct effect of
the FMD outbreak on the statistical integrity of the trial is
confined to an extension of the date by which conclusions may
be expected, but we are very concerned at the consequent delays
in data collection and compilation.
Following the delays caused by FMD, we have
worked closely with Defra to get the research programme, and badger
field trial in particular, back on course. Defra's Wildlife Unit
(WLU) has performed admirably in meeting the revised trial timetable
and we were very encouraged that all initial proactive culls are
now complete and all 10 triplets are operative. Substantial progress
has been made with some other parts of the research programme.
This includes putting in place an epidemiological study of post
FMD restocked farms in trial areas, some of which can be expected
to breakdown with TB, plus all farms outside trial areas that
restock and subsequently breakdown. This will provide a unique
set of epidemiological data that could not have been gathered
in any other way.
A sub-group of the ISG has also undertaken a
vaccine scoping study to assist in advising Defra Ministers on
the feasibility of pursuing a TB vaccination strategy for either
cattle or wildlife. A final report is expected to be submitted
to Ministers in March 2003.
Regrettably, there are some elements of the
research programme that have experienced delays, where objectives
have not been met, and that cause considerable concern. The TB99
epidemiological survey, which the Group from the outset emphasised,
is of fundamental importance to the TB research programme has
been seriously compromised. It was designed to provide data, not
only to complement that from the badger field trial, but also
to inform Government and farmers on a range of likely risk factors,
including advice on husbandry. There has unfortunately been a
considerable shortfall in the number of TB99 forms completed on
breakdown farms, and more seriously, control data from farms without
breakdowns, which are necessary for a meaningful study, remain
uncollected in many cases. We recognise that Classical Swine Fever
(CSF) and FMD reduced seriously the SVS's capacity to collect
the data required. However, we regret that the Group must advise
that while it may in the near future have the minimum data to
undertake a preliminary analysis of the TB99 study in trial areas,
that much data will have been lost and that, in part at least,
this is due to localised delays in completing forms that cannot
be entirely attributed to either CSF or FMD. We have discussed
with Defra how more complete data can be collected from at least
the trial areas. There have been recent improvements in throughput,
following the input of additional resources, and a fuller analysis
of the position will be included in the impending report to Ministers
referred to above.
The reactive strategy has also experienced serious
delays. The trigger for a reactive cull is a disclosing (positive)
herd test. FMD caused a significant backlog in testing, with inevitable
delays in initiating the reactive strategy, but this difficulty
has been compounded by delays in the WLU being informed of breakdowns
in trial areas, some of which preceded the outbreaks of CSF and
FMD, making it even more difficult for the WLU to forward plan
its operations.
The Road Traffic Accident survey of badger carcasses,
which was very slow to get off the ground, has also been affected
by FMD. The use of contractors over the last year has improved
the position and targets are nearer to being met, but the Group
still has insufficient data for robust scientific analysis. Again
our report to Ministers will set out the position in more detail.
As the Committee will be aware, the ISG has
long recognised the critical need for an improved diagnostic test
for TB, irrespective of what future policy options might be adopted.
For these reasons we have strongly advocated work to refine the
gamma interferon test, and have proposed and supported plans for
a field trial of the currently available test, to provide the
data necessary both to assess its merits and to determine how
it could best be used in a range of potential policy options.
Against this background, we were disappointed that Defra proceeded
with plans for a gamma interferon pilot and ignored the advice
of the Group without any discussion. We are assured, by the Minister,
that although the pilot has started, our concerns about its design
are now being considered seriously to ensure that scientific rigour
is applied, that essential data are forthcoming, and that the
use of scarce resource is maximised.
Looking ahead despite the many problems and
setbacks that we have had to face we believe that the research
programme that has been put in place will provide the necessary
scientific information for evaluating the impact of different
disease control measures on the bovine TB problem.
I hope that this very brief summary is helpful
in enabling your Committee to focus on key issues. We look forward
to appearing before you to explain matters in greater detail.
If you require anything further before then please let me know.
18 February 2003
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