| A
new technique for vaccinating large groups of animals has been tested
by researchers at the Universities of Glasgow, Edinburgh and Oxford -
and the results of their work could have far-reaching implications for
species in danger of being wiped out by disease.
The findings of the research led by Dr Dan Haydon from the Institute
of Biomedical and Life Sciences, along with Dr Louise Matthews from the
Faculty of Veterinary Medicine, will feature on the cover of this week’s
Nature magazine.
Rather than vaccinating the majority of a group of animals against disease,
as is traditional, they found that by targeting just 30%, the
spread of an outbreak could be curtailled.
Dr Haydon said:
“ Widespread vaccinations of large animal populations
can throw up all sorts of logistical problems. They may be spread across
large and inaccessible geographic areas and the vaccination process can
require trapping, sedation, and handling of individual animals which
some wildlife managers are uncomfortable with.
_ Theoreticians have devoted a lot
of effort to working out how to vaccinate populations in ways that
prevent epidemics getting started,
but this requires a level of coverage that is often impractical in wild
populations.
_ We’ve looked at vaccination strategies that don’t
prevent all outbreaks, but do reduce the chances of really big outbreaks – ones
that could push an endangered population over the extinction threshold.
These strategies turn out to be effective and a lot more practical.”
Along with representatives from Oxford University and University of
Edinburgh, they demonstrated that by vaccinating just thirty per cent
of the Ethiopian wolf population – the rarest carnivores in the
world – they could reduce the spread of rabies during an outbreak
and consequently, the number of animals that die from the disease.
Their study suggests that by vaccinating wolf packs living in the connecting
mountain valleys close to the outbreak, they can contain disease outbreaks
with unexpectedly low overall levels of vaccine coverage.
The findings may provide a new approach for vaccinating other populations
of endangered wild animals.
The population of just 500 Ethiopian wolves can only be found in remote
mountain enclaves in the Ethiopian Highlands.
Canid diseases, such as rabies and distemper, are the major killers,
with domestic dogs being the main disease-carriers.
After rabies outbreaks in the Bale Mountains in the early 1990s wiped
out three quarters of the Ethiopian wolf population in this area, an
emergency vaccination programme was introduced in 2003 in response to
yet another outbreak that year.
Analysis suggested that a preventative strategy to capture and vaccinate
the whole population was impractical as the wolves live in remote, inaccessible
mountainous areas.
The alternative strategy is an effective reactive response to outbreaks,
whereby Ethiopian wolves living in the mountain valleys close to infected
packs are targeted. Such strategies are likely to become cheaper and
more easily implemented with the development of protocols for the delivery
of currently available oral vaccines.
Professor David Macdonald, Director of the Oxford’s Wildlife Conservation
Research Unit, said:
“ Our aim is to put innovative science to practical
use. These discoveries would have been impossible without long-term field
studies, and they show how cutting-edge science can have down-to-earth
practical significance.”
This Glasgow-led study builds on the long association the University
has had with many African countries and comes at a time when the University
is developing even stronger ties with African academics and scientists
through its recently formed Glasgow University Africa Group. This group
supports the University’s links with Africa through research, teaching
and fund raising.
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those of IvyRose Ltd.. Material in this news item was released by Glasgow
University (Scotland, UK) on 11 October
2006 and may have been edited (e.g. in style, length, and/or for ease
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