Foot-and-mouth vaccines not up to the job says infectious disease expert


EXISTING foot-and-mouth vaccines are not good enough to deal with any future
outbreak no matter what strategy is used says a report published today.

Nor would they have dealt with last year’s epidemic, said Professor Mark
Woolhouse of Edinburgh University’s Centre for Infectious Diseases, one of
the authors of the paper in Nature.

But given improved vaccines Woolhouse and his colleagues, including Mike
Keeling of the University of Warwick, suggest that there are several
possible ways of controlling a future outbreak.

Using results from an individual farm-based computer model, the scientists
considered a national precautionary prophylactic vaccination campaign and
combinations of reactive vaccination and culling strategies during an

Prophylactic vaccination could greatly reduce the potential for a major
epidemic, they say. But it would not control any outbreak completely and
would be expensive.

Targeting high-risk farms would be much more efficient: "Given sufficient
resources and preparation, a combination of reactive vaccination and culling
might control ongoing epidemics," they say.

The team also modelled a reactive ,"predictiv" vaccination strategy,
targeting probable disease transmission hotspots which would greatly reduce
the "tail" of lingering cases which characterises FMD epidemics.

Woolhouse said yesterday that in previous FMD outbreaks such as last year,
ring vaccination had been suggested. That was ineffective and too little,
too late. He said: "We did not think it would work at the time last year and
analysis since has confirmed that."

Instead, he and his colleagues suggest alternatives. The first would be a
mass reactive vaccination programme activated as quickly as possible after
the first case is identified.

That, said Woolhouse, would mean a stand-by force able to move into action
and vaccinate hundreds of thousands of animals a day.

"It has been done and could be done, but needs stocks of vaccine ready to
use, effective and rapid distribution and a precise plan."

That was the brute force approach, he said. It would be expensive - but not
when compared with the cost of a cull such as last year’s.

The clever approach, he said, would be to identify the farms most at risk
using knowledge of risk factors for susceptibility to, and onward
transmission of, infection then target these farms with vaccination

Unfortunately, more information is needed to do that than scientists have at
present. Woolhouse said: "We learned an enormous amount from last year’s
outbreak, but we have much more to learn and we continue to analyse."

Vaccination was a contentious issue throughout, and long after, last year’s
FMD epidemic. Woolhouse said: "We did not have the right vaccines. We still
don’t. The vaccines we have now would not control the disease, they’re not
good enough."

The findings published online by Nature are part of research programmes at
the universities of Edinburgh, Warwick and Cambridge involving FMD
specialists who were members of the chief scientist’s FMD advisory group in

The work is funded by a #500,000grant from the Wellcome Trust for the
development of evidence-based control programmes. The research will help,
say scientists, make the recommendations of the Royal Society of Edinburgh
for FMD control in Scotland a reality.

Woolhouse said: "This paper points to the possibility of using combined
culling and vaccination strategies for coping with foot and mouth epidemics
in future."

Culling - slaughter - would still be an essential part of control, he said.
He went on: "We need a wide scale infrastructure and planning to ensure that
control can be implemented as soon as the disease is detected... but we also
need more effective vaccines if we are to eliminate the threat of
foot-and-mouth disease."

Last week the European Commission published a directive for more effective
control of future outbreaks of FMD.

David Byrne, commissioner for health and consumer protection, underlined the
need to strengthen current control measures and said that lessons had been
learned from last year's outbreak, which affected Holland, France and
Ireland as well as the UK.

Byrne said that emergency vaccination now moves to the forefront of control
measures whereas in the past, it was widely regarded as a last resort.

The new control measures will ensure a much higher level of preparation
against outbreaks of the disease, he said. The draft directive sets out
procedures for the use of emergency vaccination, and information on to how
to regain "free from FMD" status once the outbreak has been brought under

The "regionalisation" of measures is introduced, whereby restrictions are
imposed only on the particular regions of a member state affected by an
outbreak. However, the proposals keep in place a strict eradication policy
in relation to infected herds and the ban on routine preventive vaccination
will continue.