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Published Date: 2006-05-10 00:00:00
Subject: PRO/AH/EDR> Avian influenza - worldwide (108): Denmark, Germany
Archive Number: 20060510.1341

AVIAN INFLUENZA - WORLDWIDE (108): DENMARK, GERMANY
***************************************************
A ProMED-mail post
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ProMED-mail is a program of the
International Society for Infectious Diseases
<http://www.isid.org>
In this update:
[1] Germany, wild birds, update 3 May 2006
[2] Denmark, wild birds, update 8 May 2006
[3] Europe, Africa, wild birds, News story
******
[1] Germany, wild birds, update 3 May 2006
Date: Wed 10 May 2006
From: Thomas Roesel <roesel@lycos.com>
Source: Friedrich Loeffler Institute Epidemiology Bulletin, 3 May
2006, accessed 9 May 2006 [translated by submitter, edited]
<http://www.fli.bund.de/fileadmin/user_upload/Dokumente/News/aktuelle_Krankheitsgeschehen/avi_Flu/LB_Influenza.pdf>

339 cases of avian influenza in wild birds from [the entire territory
of] Germany have been confirmed by the Friedrich Loeffler Institute
(FLI) as of 3 May 2006.
During the period 26 Apr 2006 to 3 May 2006, the following 9 new
cases were confirmed:
Municipality / Administrative or City District / State / Species /
Date H5N1 confirmed
Letschin / Maerkisch-Oderland / BB* / White Stork / 3 May 2006
Harburg / Danube-Ries / Bavaria / Swan / 2 May 2006
Molfsee / Rendsburg-Eckernfoerde / SH** / Crested Grebe / 2 May 2006
Denklingen / Landsberg on the Lech / Bavaria / Merganser / 28 Apr 2006
Parkstetten / Straubing (town) / Bavaria / Mute Swan / 28 Apr 2006
Kirchroth-Nierachdorf / Straubing (town) / Bavaria / Mute Swan / 26 Apr 2006
Kirchroth-Muenster / Town of Straubing / Bavaria / Mute Swan / 26 Apr 2006
Letschin / Maerkisch-Oderland / BB / White Stork / 26 Apr 2006
Bautzen (Neumalsitz) / Bautzen / Saxony / Wild Duck / 26 Apr 2006
* Brandenburg
** Schleswig-Holstein
[The submitter kindly indicated that the wild duck found at Bautzen,
in the above message, was reported as a tufted duck by the Free State
of Saxony (posting 20060427.1226); the white stork found at Letschin
on 26 Apr 2006 was already included in the said report].
--
Thomas Roesel
<roesel@lycos.com>
[The above URL (in German) includes maps showing the collection sites
of the dead birds.
Are we witnessing a decreased incidence of infection in wild birds in
Europe, indicating that the peak is over? (See also the following
item on Denmark and the news story below). If affirmative, is this
just a seasonal, temporary decline? The following excerpts from the
introduction to a review paper (currently in print) by 2 leading AI
authorities highlight some of the present gaps in the needed
knowledge.
Ilaria Capua and Dennis J. Alexander (2006). The challenge of avian
influenza to the veterinary community. Avian Pathology 2006, 1_/17,
Preview article.
"Prior to the ongoing H5N1 epizootic, HPAI had only once affected
wild birds significantly. This outbreak occurred in South Africa in
1961 and caused the death of approximately 1300 common terns [Becker,
W.B. (1966). The isolation and classification of tern virus:
influenza virus A/tern/South Africa/1961. Journal of Hygiene, 64,
309-320]. It appeared that HPAI was a disease of domesticated birds
and that wild birds usually only harbored the low-pathogenic form of
these viruses.
The unprecedented situation occurring in Asia has resulted in the
spill-over of infection to naive populations of wild birds. Although
to date all these birds were either dead or dying, the incubation
period of this disease in Asian migratory birds is unknown and
probably shows considerable variability among families and species.
In very simple terms, at the moment, the scientific community only
has an indication of the species that may be infected and succumb to
the virus. Knowledge and information on all species that are
susceptible to infection, including the incubation period for those
birds that do develop a clinical condition, their ability to fly
significant distances if infected and data on the route, duration and
titre of viral shedding, are unavailable.
At this stage, only hypotheses can be formulated on the
eco-epidemiological consequences of this spill-over. At the moment,
it is unclear whether or not HPAI H5N1 is truly endemic in the
Eurasian wild bird population or merely limited to spill-over events
from domestic birds. If the latter is true, then provided the
domestic source of infection is eliminated, and the infections are
responsible for the death of the wild avian hosts, presumably the
prevalence of infection will gradually be reduced to zero. In
contrast, if HPAI infection does not bring about the death of the
wild bird host and becomes compatible with normal behavioral patterns
and migration in at least some species, this will result in the
development of an endemic cycle in wild birds, mimicking the
well-known LPAI ecology. The consequences of such a situation are
unpredictable."
- Mod.AS]
******
[2] Denmark, wild birds, update 8 May 2006
Date: Wed 10 May 2006
From: ProMED-mail <promed@promedmail.org>
Source: Danish Veterinary & Food Administration - News website,
accessed 10 May 2006 [edited]
<http://www.uk.foedevarestyrelsen.dk/AnimalHealth/Avian_influenza/Latest_news/forside.htm>

On 8 May 2006, the protection and surveillance zones surrounding
Aero, Drejo, Svendborg, Faborg and Ullerslev in Funen County were
removed. There are no more [protection and surveillance] zones in
Funen County.
On 5 May 2006, the protection and surveillance zones surrounding
Praesto in Storstrom County were removed. There are no more zones in
Storstrom County.
On 4 May 2006, the following zones were removed:
- Protection and surveillance zones surrounding Frederikssund and
Skibby in Frederiksborg County. There are no more zones in
Frederiksborg County.
- Protection and surveillance zones surrounding Sonderborg and
Kegnaes in South Jutland County.
On 3 May 2006, the protection and surveillance zones surrounding
Hornbaek in Frederiksborg County were removed.
On 2 May 2006, the Danish Veterinary and Food Research Institute
detected high pathogenic avian influenza (H5) in a great crested
grebe (_Podiceps cristatus_), which was found in the town Grasten in
South Jutland County.
The Danish Veterinary and Food Administration is implementing
measures in accordance with Commission Decision 2006/115/EC,
including establishing protection and surveillance zones. Grasten is
located within the surveillance zone established on 29 Mar 2006 in
South Jutland County.
--
ProMED-mail
<promed@promedmail.org>
[Between 14 Mar 2006 -- when the 1st HPAI H5-infected wild bird (a
Common buzzard) was confirmed in Denmark -- and 2 May 2006 -- when
the (so far) last case was confirmed (a great crested goose) -- the
Danes identified a total of 43 infected wild birds. They were:
26 Tufted ducks (_Aythya fuligula_)
6 Common buzzards (_Buteo buteo_)
4 Mute swans (_Cygnus olor_)
3 Whooper swans (_Cygnus cygnus_)
1 Peregrine falcon (_Falco peregrinus_)
1 Rough-legged buzzard (_Buteo lagopus_)
1 Greylag goose (_Anser anser_)
1 Great crested goose (_Podiceps cristatus_)
According to the Danish website, 716 dead wild birds were tested for
the presence of avian influenza at the Danish Veterinary and Food
Research Institute during the 1st 3 months of 2006.
The birds have been grouped into the categories:
- Predatory birds (Buzzards, Eagles, Falcons, Hawks and Owls)
- Swans
- Ducks
- Other swimming birds
- Gulls and terns
- Crow birds
- other birds
The web page includes a histogram showing the number of birds that
have been tested in each category and the infection rate among them.
These data relate to the period January-March 2006. The site includes
also a map showing the collection sites of these dead birds. See
<http://www.uk.foedevarestyrelsen.dk/AnimalHealth/Avian_influenza/Latest_news/Results_in_2006/forside.htm>.
It would be useful if surveillance systems on AI in wild birds and
their results, such as the exemplary Danish ones, could be compared
with similar data from other countries, within and outside Europe. To
this end, common denominators, standardized collection and testing
methods, and the use of scientific terminology (species names) are
prerequisites. Hopefully, the FAO/OIE International Scientific
Conference on Avian Influenza (AI) and Wild Birds, due in Rome later
this month (May 2006), will help in bridging the concerning gaps in
knowledge which were mentioned above. - Mod.AS]
*******
[3] Europe, Africa, wild birds
Date: 10 May 2006
From: ProMED-mail
Source: International Herald Tribune/NY Times Online [Edited]
<http://www.nytimes.com/2006/05/10/health/10cnd-flu.html?hp&ex=1147320000&en=9ba789771e56ce4b&ei=5094&partner=homepage>
Birds Return to Europe Without Virus
-----------------------------
The flocks of migratory birds that winged their way south to Africa
last autumn and then back over Europe in recent weeks did not carry
the H5N1 flu virus or spread it during their annual journey,
scientists have concluded, defying health officials' dire predictions.
International health officials had feared that the disease was likely
to spread to Africa during the winter migration and return to Europe
with a vengeance during the reverse migration this spring. That has
not happened - a significant finding for Europe, because it is far
easier to monitor a virus that exists domestically on farms, but not
in nature.
"It is quiet now in terms of cases, which is contrary to what many
people had expected," said Ward Hagemeijer, an avian influenza
specialist with Wetlands International, an environmental group based
in the Netherlands that studies migratory birds.
In thousands of samples collected in Africa this winter, H5N1 was not
detected in a single wild bird, officials and scientists said. In
Europe, there have been only a handful of cases detected in wild
birds since April 1, at the height of the northward migration.
The number of cases in Europe has decreased so dramatically compared
to February, when dozens of new cases were found daily, that experts
believe the northward spring migration played no role. There was one
grebe in Denmark on April 28 - the last case - as well as a falcon in
Germany and a few swans in France, according to the World
Organization for Animal Health, based in Paris.
In response to the good news, agriculture officials in many European
countries have this month lifted restrictions designed to protect
valuable domestic poultry from infected wild birds.
In the first week in May, both the Netherlands and Switzerland
rescinded mandates that poultry be kept indoors. Austria has loosened
similar regulation and France is considering doing so, as farmers
(and their poultry) chafe under the restrictions of indoor life as
the weather warms.
The February cases in Europe were attributed to infected wild birds
that traveled west to avoid severe cold in Russia and Central Asia
but apparently never carried the virus on to Africa. The
international scientists who had issued the prior warnings are
perplexed, unsure if their preventive measures - like intensive
surveillance and eliminating contact between poultry and wild birds -
helped defuse a time bomb, or if nature simply granted the reprieve.
And they warn that H5N1 could return to Europe in the future.
"Is it like Y2K, where also nothing happened?" asked Juan Lubroth, a
senior veterinary official at the United Nation Food and Agriculture
Organization in Rome, referring to the expected computer failures as
the year 1999 turned to 2000. "Perhaps it is because it was not as
bad as we feared, or perhaps it is because people took the right
measures."
Still, he and others say, the lack of wild bird cases in Europe only
underscores how little is understood about the virus.
"Maybe we will be lucky and this virus will just die out in the
wild," Dr. Lubroth said. "But maybe it will come back strong next
year. We just don't have the answers."
The feared H5N1 bird flu virus is not easily spread among humans,
although scientists are worried it may acquire that ability through
natural processes, setting off a worldwide flu pandemic. The less
bird flu is present in nature and domestically on farms, the less
likely it is for this evolution to occur, they say.
Worldwide, it has killed about 200 humans, almost all people who were
in extremely close contact with sick birds.
Specialists from Wetlands International, who were deputized by the
Food and Agriculture Organization, sampled 7,500 African wild birds
last winter in their search for the disease. They found no H5N1, Mr.
Hagemeijer said, so it is not surprising that H5N1 did not return to
Europe with the spring migration.
While avian influenza has become a huge problem in domestic poultry
on farms in a few African countries, like Egypt, Nigeria and Sudan,
experts increasingly suspect that it was introduced there through
imported infected poultry and poultry products.
Mr. Hagemeijer thinks that the virus's strength among wild birds may
have weakened as the southward migration season progressed - a trait
common in less dangerous avian influenza viruses, he said. That
probably limited its spread to Africa, he said.
H5N1 is the most deadly of a large family of avian influenza viruses,
most of which produce only minor illness in birds.
Many avian influenza viruses are picked up by migratory birds in
their nesting places in northern lakes during the summer and autumn
breeding season. As the months pass, the viruses show a decreasing
pattern of spread and contamination.
"So it tends to be mostly a north-to-south spread, and then it wanes," he said.
Still, this means that the cycle could well start again this summer,
if the H5N1 virus - which can live for long periods in water - has
persisted in those breeding areas. Many bird specialists believe that
a small number of wetland lakes in Central Asia and Russia may harbor
the H5N1 virus all the time, serving as the origin of European and
Central Asian infections.
In fact, so much remains uncertain about the path of the virus that
the European Union and some countries, like Germany, have decided to
keep at least some precautions in place. Germany this week extended a
law, due to expire May 15, that keeps poultry inside if they live
near wetlands or in other areas that have had bird flu cases.
"There is still no systematic risk assessment - we've tested
thousands of birds, but really tens of thousands need to be tested,"
Mr. Hagemeijer said.
Scientists still do not know which birds carry the virus silently and
which die from it quickly, or also how it typically spreads from wild
bird to wild bird, or between wild birds and poultry.
At the Beijing donor conference sponsored by the World Bank, $1.9
billion was pledged. "But none of it was for researching the role of
wild birds," Mr. Hagemeijer said. "It was all for stockpiling
Tamiflu" - the anti-viral drug for use against bird flu.
The disappearance of the virus from wild birds in Europe would be
important, nonetheless, because it is easier to monitor a virus that
exists only on farms.
Farm-based outbreaks of avian influenza are still occurring
constantly in a number of countries, although not in Europe. The
Ivory Coast had its first outbreak of bird flu, on a farm, last week.
But other countries, like Turkey, have made good progress in
containing the disease among poultry, Dr. Lubroth said. He added that
he hoped that quick measures to limit outbreaks had reduced its
spread in Africa.
After the disease was found on farms in Nigeria in January, most
experts expected it would spread rapidly among farms and into wild
birds in the region. Apparently, it did not.
"Why didn't it sweep up the coast from Niger, to Benin and Senegal
and back up through Europe? Why didn't it hit Africa's big lakes?"
Dr. Lubroth asked.
"All we have are a few snapshots of the virus. What we need is a
movie of its life cycle."
[Byline: Elisabeth Rosenthal]
--
ProMED-mail
<promed@promedmail.org>

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