Wild Birds' Role In HPAI Crisis Confirmed - But Scientific Conference Fingers Poultry Business
Article Date: 04 Jun 2006 - 10:00am (PDT)
Migrating
wild birds have played and will likely continue to play a role in
transporting highly pathogenic avian influenza (HPAI) virus, or bird
flu, over long distances. This was among the main conclusions of a
two-day international scientific conference called by the UN Food and
Agriculture Organization and the World Organisation for Animal Health
(OIE).
But the conference, attended by over 300 scientists
from more than 100 countries also recognized that the virus was mainly
spread through poultry trade, both legal and illegal.
“Several presentations at the Conference, some supported by recent
publications in peer-reviewed scientific journals, implicated wild
birds in the introduction of HPAI H5N1 virus at considerable
geographical distance from known H5N1 outbreaks in poultry,” the
meeting said in a concluding document.
Reservoir puzzle
But the participants admitted they could not resolve another of the key
issues at the conference, which was the role of wild birds in the
spread of HPAI to more than 50 countries on three continents, and
whether wild birds should now be considered a permanent reservoir of
the virus.
If they are such a reservoir, there is a strong likelihood they will
carry the virus with them in subsequent migrations. Alternately H5N1
may subside naturally as infected animals die off, or it may mutate to
a less aggressive form.
“This was one of the main gaps identified in our present scientific
knowledge,” said Joseph Domenech, FAO's chief veterinary officer. “We
must therefore intensify our investigations.”
The conference noted that the current outbreaks of H5N1 virus in eight
African countries appeared to be poultry-related and chiefly based on
trade in poultry for human consumption, including illegal trade.
However, it called for further analysis for a more complete
understanding of how the virus was introduced.
More investment
"There is a need to mobilize the international donor community to
invest in the improvement of veterinary services in developing
countries, especially in Africa and Asia,” Dr Gideon K. Brückner, Head
of OIE's Scientific and Technical Department, said.
Wise investments here will promote early detection in wild birds and rapid response to disease outbreaks, Dr Brückner added.
H5N1 disease management would need to be based on improved biosecurity
and hygiene at the production level, and in all poultry sectors,
including minimizing the possibility of contact between domestic and
wild birds, the conference advocated.
It called for the establishment of a global tracking and monitoring
facility involving all relevant institutions across the world,
including scientific centers and farmers'organizations, hunters, bird
watchers, and wetland and wildlife conservation societies.
The participants rejected any suggestion of trying to stop the spread
of HPAI by killing wild birds. “Destruction of wild bird habitats or
indiscriminate hunting of wildlife is scientifically and ethically
unjustified as a response,” one of the conference recommendations said.
It urged continuing research to adopt an inter-disciplinary approach,
and called for investment to incorporate telemetry/satellite technology
to improve understanding of wild bird migration patterns (see related
article “Free as a bird - or under surveillance”).