A MODEL DECISION

June 6, 2001

Why, a farmer asks, did the government ignore its advisers?

Alan Beat
Wednesday
The Guardian (“Society” section, p. 9)
http://www.societyguardian.co.uk/societyguardian/story/0,7843,501849,00.html

Three weeks ago in the Veterinary Record, the head of the government's
research faculty argued that the government's response to foot and mouth -
the contiguous cull policy - was unnecessary.

Alex Donaldson, director of Pirbright laboratory at the Institute for Animal
Health, argued that airborne transmission of the foot and mouth virus
between livestock was limited to short distances of less than 100 metres,
that the contiguous cull was unnecessary and that monitoring of livestock
considered to be at risk should replace slaughter on suspicion.

Anthony Gibson, regional director of the National Farmers Union (NFU) in the
south-west, describes it as "the most damning indictment yet of the govern-
ment's controversial contiguous cull policy.

"The contiguous cull has been exposed for what it was; one of the most
bloody, tragic and disgraceful misjudgments ever committed in the name of
science," says Gibson.

Donaldson's revelations carry considerable weight because of his position as
head of the government's own research faculty, and his status as one of the
world's leading authorities on foot and mouth.

But his latest article merely updates work published the year before. And
since Donaldson himself sits on the government's scientific advisory
committee, it is inconceivable that this was not put before the assembled
experts for consideration.

"An integrated model to predict the atmospheric spread of foot- and-mouth
virus" was published last year in the scientific journal Epidemiology and
Infection. The paper, which Donaldson co-authored with three others
specialists, described in detail the development of computer modelling
software that combines meteorological input with foot and mouth disease data
to predict the direction and distance that the airborne virus may travel.
Using historical records from two previous disease outbreaks it "predicted"
the known spread of virus. The model was also used to predict the risk of
infection spreading from livestock on one farm to another, using existing
data drawn from a wide range of published research.

The authors conclude that "transmission from infected cattle or sheep could
not be shown to occur over distances of more than about 3km."

Were the extended cull and firewall policies introduced to Cumbria and the
Scottish borders with a 3km limit based on this very prediction? If so, it
is confirmation that the scientific advisory committee were familiar with,
and were utilising, the information contained in the paper.

However, this 3km distance was a "worst case" scenario, applicable only to
cattle, and only when 1,000 infected cattle or sheep were positioned upwind.
The corresponding distance for risk of infection in sheep was 500 metres.
During a high-profile epidemic, such huge numbers of infected stock cannot
pass undetected and a more realistic limit would lie between 10 and 100
infected animals on any one farm.

At this more practical upper limit of 100 infected animals, the maximum
distance over which cattle were predicted to be at risk was 700 metres,
while for sheep this reduced to less than 100 metres. For a more typical
farm situation of 10 infected animals, where the signs of disease were
promptly seen, the distance of risk reduced further to less than 100 metres
for both cattle and sheep.

These were the distances predicted by the best available veterinary science.
Yet the scientific advisory committee recommended a draconian policy of 3km
or contiguous culls. Why?

The prime minister said that there was no alternative to this policy. The
minister for agriculture, Nick Brown, stated repeatedly in the House of
Commons that government policy "was based on the latest scientific and
veterinary advice".

The unpalatable truth is that the best veterinary scientific advice was
ignored by those responsible for formulating government policy. Instead,
they favoured the computer modelling of university-based epidemiologists who
proposed the spread of disease by making assumptions about a hypothetical
"standard" livestock species, and about the statistical chance of spread to
neighbouring animals, which had no factual basis in veterinary science.

Can there be any doubt that this science was placed before top- level
meetings involving the prime minister, the minister for agriculture, the
chief scientific officer and others responsible for formulating policy,
since Donaldson was included in these discussions?

It is also impossible to believe that the NFU hierarchy were unaware of
these facts, since they too were involved at the highest levels of
consultation throughout.

I believe there has been a major error of the highest order. The only
remaining question is - why did it happen?

Alan Beat is a smallholder in Devon with 24 sheep and has resisted the cull
for seven weeks. alan.beat@talk21.com