Supplementary memorandum submitted by
Martin Hancox
BOVINE TB
1. Further to the Oral Session of 26 May,
and media coverage since, might I make a brief comment which could
perhaps bring some light into the pervasive darkness. I was very
surprised that neither your 10th December 2003 nor 26th May sessions
with both Minister Ben Bradshaw and Professor Bourne of ISG really
challenged the DEFRA claim that reactive badger culls made cattle
TB 27% worse. Nor has Professor Godfray been called to explain
why he challenges this view, and, having seen the full data, why
he URGES that this be released to Ministers/DEFRA NOW
to inform the three ongoing TB Consultations. Bourne's response
to Godfray makes the critically important admission that far from
a 20% drop in cattle TB due to culls, "A reduction of A FEW
PERCENT in breakdown rates, THE MOST that is even remotely consistent
with the data, will (this) be of any practical value or interest?"
2. Based on DEFRA data, if there are only
one infectious badgers per 6 km2 from culls then even "a
few percent" contribution to cattle TB seems optimistic.
Given the cull of 2,066 reactive and 6,313 proactive, or 8,400
badgers so far (January 2004), there must be data on prevalence
of infectious badgers versus TB herds (NVL/VL reactors) spatio-temporally.
The reactive ones were stopped prematurely, and have flaws, eg
nearly two years between breakdown and cull, but must yield some
data on the links. Not as good as the clean ring data however:
most breakdowns in new areas, caused by imported index cattle,
with diminishing badgers with TB going outwards from the epicenter,
until reaching a clean ring with no TB badgers or cattle. Proactive
culls are much less closely associated with breakdowns, so will
culling another few thousand yield any significant data? Cost
to 2006 or 2008 another £21 or £35 million, much better
spent on increased cattle testing and recruiting more vets.
3. Neither Godfray nor Bourne/ISG seem aware
of the pivotal flaw in their statistical analyses. These assume
breakdowns occur independently in a Poisson distribution but repeat
and contiguous cattle-to-cattle spread breakdowns in hotspots
are very clearly linked ie NON-Independent. Hence the range from
minus 2 to plus 65% (average 27) which includes zero, ie NIL effect
of badger culls, or a result by chance (Godfray). Given such a
low (or NIL) badger contribution to cattle TB, no cull or vaccination
strategy will ever be meaningful or cost-effective.
Martin Hancox
June 2004
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