H5N1 could become endemic in parts of the region – virus
search in domestic ducks and geese crucial.
The avian influenza virus H5N1 could become entrenched in chickens
and domestic ducks and geese in parts of Europe, FAO warned today.
The agency stressed that healthy domestic ducks and geese may
transmit the virus to chickens and play a more important role in
the persistence of the virus in the region than previously thought.
H5N1 surveillance in countries with significant domestic duck and
geese populations should be urgently increased.
FAO’s warning followed the detection of H5N1 in diseased
young domestic ducks by German scientists.
“It seems that a new chapter in the evolution of avian influenza
may be unfolding silently in the heart of Europe,” said FAO’s
Chief Veterinary Officer, Joseph Domenech. “If it turns out
to be true that the H5N1 virus can persist in apparently healthy
domestic duck and geese populations, then countries need to urgently
reinforce their monitoring and surveillance schemes in all regions
with significant duck and geese production for the presence of
“Europe should prepare for further waves of avian influenza
outbreaks, most probably in an east-west direction, if the virus
succeeds in persisting throughout the year in domestic waterfowl.
This heightens the need for increased surveillance and monitoring
of possible virus circulation in domestic ducks and geese,” Domenech
Ducks and geese
The link between domestic ducks and geese and chickens is seen
by many experts as one of the major underlying factors in outbreaks
of HPAI in disease-entrenched countries.
“We are particularly concerned about the Black Sea area
which has a high concentration of chickens, ducks and geese,” said
FAO senior animal health officer Jan Slingenbergh.
“In the Ukraine alone, the number of domestic ducks is estimated
at around 20 million birds. In Romania, four million domestic ducks
and four million domestic geese are found in the Danube delta.
These figures compare easily with chicken and waterfowl densities
in Asia, where the virus continues to circulate among chickens
and has found a niche in countries with tens of millions of domestic
ducks and geese,” Slingenbergh said.
Importantly, the Black Sea area serves as a main wintering area
for migratory birds coming from Siberia and moving also to the
Mediterranean and other regions. All countries bordering the Black
Sea have experienced outbreaks of avian influenza in the past,
favoured by traditional open poultry systems with poor separation
between wild and domestic birds.
The German case
The link between the H5N1 virus and domestic ducks and geese has
recently been confirmed in Germany.
Scientists of the Friedrich-Loeffler-Institut in Riems have detected
the H5N1 virus in diseased young ducks on a farm at the end of
August. Further scrutiny at two other farms revealed that, despite
the absence of clinical signs and mortality in these ducks, the
animals had been in contact with the H5N1 virus, because their
immune defense system showed antibodies, developed in response
to the virus. Intensified monitoring finally confirmed pockets
of H5N1 on one of the farms.
Based on its experience in fighting avian influenza around the
world over the past three years, FAO considers that risk assessment,
surveillance and virus search strategies should be reviewed, Domenech
Countries with significant domestic duck and geese populations
in Western and Central Europe as well as the Black Sea region should
consider the incidence in Germany as a wake-up call and should
not limit the virus search to chickens. Good surveillance is already
in place in many European countries and the European Commission
has issued in 2007 very comprehensive guidelines.
But there are countries where more monitoring is urgently needed
including more focus on ducks and geese which should be considered
as particularly risky populations.
“It could well be that there is more virus circulation in
Europe than currently assumed,” Slingenbergh said. “We
are not saying that the virus is widely spread in European countries,
in fact most of the countries are currently virus-free. But undetected
localized virus spots in countries with significant waterfowl may
pose a continuous risk.”
After Asia and Africa, Europe could become the third continent
where the H5N1 could become endemic in some areas, FAO said.
Announces Boost for FAO’s Bird
RABDF Welcomes Chief Scientist’s Support
for Badger Cull
RABDF/Defra Farm Health Planning Award 2007