Published Date: 2007-12-07 15:01:24
Subject: PRO/AH/EDR> Avian influenza, poultry vs migratory birds (37): Europe
Archive Number: 20071207.3947
AVIAN INFLUENZA, POULTRY, MIGRATORY BIRDS (37): EUROPE
******************************************************
A ProMED-mail post
<http://www.promedmail.org>
ProMED-mail is a program of the
International Society for Infectious Diseases
<http://www.isid.org>
Date: Fri 7 Dec 2007
Source: Eurosurveillance weekly release, 2007 12(12) [edited]
<http://www.eurosurveillance.org/ew/2007/071206.asp#1>
Since the emergence of A/H5N1 in the winter of 2005-2006 at the
border of the European Union (EU), including human cases in Turkey,
the European Centre for Disease Prevention and Control (ECDC) has
developed assessments on the public health risks from A/H5N1, and
guidance on how to protect those that may be exposed to the virus [1].
Over the last 3 years, the EU has also made strenuous efforts to
improve the protection of EU domestic poultry from A/H5N1 infection,
including enhancing biosecurity around domestic flocks and increasing
veterinary surveillance activities in bird populations (wild and
domestic) in order to provide an essential early warning of the
presence of the virus. [The table showing the total surveillance
activity in wild birds and poultry holdings in the European Union,
February-December 2006 and January-March 2007 is available at the source URL.]
Direct comparison of surveillance activity between the 2 periods
[February-December 2006 and January-March 2007] is difficult, but the
data available to date suggest a lower surveillance activity in wild
birds in 2007 compared to 2006. There also remains large
heterogeneity in the number of wild birds tested in all the Member
States. However, the reported incidence data in 2007 are consistent
with a relatively low level of A/H5N1 virus circulation within EU
bird populations: infected wild birds have only been identified in 4
EU Member States, all within a short time-frame and a limited
geographical area in central Europe.
As of 5 Dec 2007, 307 wild birds have tested positive in the EU
during 2007. The vast majority were found in Germany (298), with
small numbers in France (7), the Czech Republic (1), and Hungary (1).
Almost all these cases were reported in a 7-week period between
mid-June and beginning of August [6]. This is in contrast to 2006,
when 14 Member States reported a total of 748 positive cases of
A/H5N1 in wild birds between February and August, indicating a
broader distribution of the virus in the EU, mostly in a wave that
rose and fell in the 1st half of the year [7].
The apparent lower level of virus circulation in wild birds during
2007 has not been reflected in the reported number of domestic
poultry outbreaks in the EU. As of 3 Dec 2007, 14 outbreaks in
domestic poultry have been reported in 6 Member States [8]. Although
3 countries (Hungary, Germany, and the Czech Republic) have also
reported cases in wild birds, the timing and location of cases in
domestic poultry offer no obvious epidemiological link to wild bird
infection in the majority of cases. This is in contrast to 2006, when
most of the 33 domestic poultry outbreaks reported in the 5 affected
Member States (Hungary (29), Sweden (1), Germany (1), Denmark (1),
and France (1)) were preceded by the positive identification of virus
in wild birds in the vicinity of the index case, giving a strong
epidemiological link to the source of infection.
It seems, therefore, that unlike 2006, where proactive surveillance
in wild birds established the presence of virus in several locations
prior to the virus being identified in poultry, epidemiological data
from 2007 did not detect infection in local wild birds before
infection in domestic flocks. This is open to various
interpretations, one being that EU wild bird surveillance, although
extensive, has not been sufficient to trace infection in wild birds.
However, in those areas where domestic flocks have been affected,
even increased retroactive wild bird surveillance around cases in
domestic poultry has, in most cases, failed to identify A/H5N1
infection in wild bird populations. This points to the possibility of
other routes of entry into domestic poultry, such as through trade in
poultry products, or via fomites. The latter has been suggested in
the linked outbreaks in Hungary and the United Kingdom (UK) in 2007 [9,10].
Conclusion
----------
Irrespective of the cause, the infrequent but indiscriminate
challenge from A/H5N1 may be the new reality that all owners of
poultry in the EU, both commercial and hobby flocks, must now adapt
to, at least in the short term. This also has important implications
for public health: the apparently increasingly sporadic outbreaks of
infection in domestic poultry, although uncommon, highlight the need
for all owners of poultry to remain vigilant for the presence of
infection in flocks. ECDC's risk assessment is that those most at
risk are people with small domestic and hobby flocks, rather than
those working on large 'industrial' farms [11], although it is
important that the prevention messages reach both. The truth of this
was shown earlier this year (2007), when an outbreak with another
less pathogenic avian influenza infection (avian influenza A/H7N2) in
poultry infected some owners, put a few people into hospital with
illness and required many more to take prophylaxis [12].
Although there have been no human H5N1 cases in the EU, there is more
than a theoretical possibility that cases will be seen in the future
and that they will come from people with small backyards or hobby
flocks. In order to minimise this risk, it is important to encourage
good hygiene practises in all who have contact with poultry,
including in particular avoiding handling sick or dead birds and
regular hand-washing following any contact with birds. This is
especially the case given the apparent uncoupling between cases
detected in wild birds and domestic poultry; wild bird sentinels may
not highlight the presence of infection before it appears in domestic
flocks. Of course, there are a number of other zoonoses that are
considerably more likely to be transferred from birds to their owners
in the EU, but the same precautions recommended to protect against
A/H5N1 will also protect against the other infections [13].
Overall, although the epidemiological interaction of H5N1 virus
between wild birds and domestic poultry may have changed somewhat
during 2007 in comparison to previous years, there is nothing in the
international data to suggest that the virus has altered its
characteristics in such a way as to increase the likelihood of
transmission to humans. The ECDC has therefore not altered its
standing risk assessment on the direct human health implications of
the A/H5N1 viruses, which is that they are, at present, a group of
influenza viruses of birds, poorly adapted to humans, whom they find
hard to infect except at high doses. They are dangerous as they are
highly pathogenic in those few humans that do become infected, but
then they generally do not transmit on to other humans [14].
References
----------
1. ECDC Technical report: Avian influenza portfolio: Collected risk
assessments, technical guidance to public health authorities and
advice to the general public, Stockholm, June 2006. Available from
<http://ecdc.europa.eu/documents/pdf/up/ECDC_TR_Avian%20Flu%20Portfolio.pdf>
2. European Commission. Health & Consumer Protection
Directorate-General: Annual report of avian influenza in wild birds
carried out by Member States (February-December 2006) prepared by the
Community Reference Laboratory for avian influenza and Newcastle
disease. Available from
<http://ec.europa.eu/food/animal/diseases/controlmeasures/avian/annrepres_surv_wb_02-12-2006_en.pdf>
3. European Commission. Health & Consumer Protection
Directorate-General: Report: surveillance for avian influenza in wild
birds carried out by Member States (January-March 2007) prepared by
the Community Reference Laboratory for avian influenza and Newcastle
disease. Available from
<http://ec.europa.eu/food/animal/diseases/controlmeasures/avian/res_ai_surv_wildbirds_2007-1_en.pdf>
4. European Commission. Health & Consumer Protection
Directorate-General. Annual report of the avian influenza
surveillance in poultry carried out by Member States
(February-December 2006) prepared by the Community Reference
Laboratory for avian influenza and Newcastle disease. Available from
<http://ec.europa.eu/food/animal/diseases/controlmeasures/avian/res_surv_wb_annual_06_en.pdf>
5. European Commission. Health & Consumer Protection
Directorate-General: Report: surveillance for avian influenza in
poultry carried out by Member States (January-March 2007) prepared by
the Community Reference Laboratory for avian influenza and Newcastle
disease. Available from
<http://ec.europa.eu/food/animal/diseases/controlmeasures/avian/res_ai_surv_poultry_2007-1_en.pdf>
6. Highly pathogenic avian influenza (HPAI) cases in wild birds in
2007 notified by Member States to the Animal Disease Notification
System (ADNS). Available from
<http://ec.europa.eu/food/animal/diseases/adns/adns_wildbirds2007.pdf>
7. Highly pathogenic avian influenza (HPAI) cases in wild birds in
2006 notified by Member States to the Animal Disease Notification
System (ADNS). Available from
<http://ec.europa.eu/food/animal/diseases/adns/adns_wildbirds2006.pdf>
8. European Commission. Health & Consumer Protection
Directorate-General. Animal Disease Notification System: Table 11:
Animal disease situation per country and per disease. Available from
<http://ec.europa.eu/food/animal/diseases/adns/table_11_2007/adns_231107_en.pdf>
9. Editorial team: Two outbreaks of H5N1 avian influenza in farm
geese, Hungary, January 2007. Euro Surveill 2007; 12(2): E070215.2.
Available from
<http://www.eurosurveillance.org/ew/2007/070215.asp#2>
10. Outbreak of highly pathogenic H5N1 avian influenza in Suffolk, UK
in January 2007: A report of the epidemiological findings by the
national emergency epidemiology group, DEFRA, 5 Apr 2007. Available from
<http://www.defra.gov.uk/animalh/diseases/notifiable/disease/ai/pdf/epid_findings050407.pdf>
11. ECDC Technical Report: The Public Health Risk from Highly
Pathogenic Avian Influenza Viruses Emerging in Europe with Specific
Reference to type A/H5N1, Version 1 Jun 2006. Available from
<http://ecdc.europa.eu/Health_topics/Avian_Influenza/pdf/060601_public_health_risk_HPAI.pdf>
12. Editorial team: Avian influenza A/(H7N2) outbreak in the United
Kingdom. Euro Surveill 2007; 12(5): E070531.2. Available from
<http://www.eurosurveillance.org/ew/2007/070531.asp#2>
13. ECDC Technical report: Avian influenza portfolio: collected risk
assessments, technical guidance to public health authorities and
advice to the general public, Stockholm, June 2006. Available from
<http://ecdc.europa.eu/documents/pdf/up/ECDC_TR_Avian%20Flu%20Portfolio.pdf>
14. ECDC technical report: The Public Health Risk from Highly
Pathogenic Avian Influenza Viruses Emerging in Europe with Specific
Reference to type A/H5N1 Version 1 Jun 2006. Available from
<http://www.ecdc.eu.int/Health_topics/Avian_Influenza/pdf/060601_public_health_risk_HPAI.pdf>
[H Needham on behalf of the Influenza Project Team
(<influenza@ecdc.europa.eu>)*, European Centre for Disease Prevention
and Control, Stockholm, Sweden
*B Ciancio, K Fernandez de la Hoz, P Kreidl, H Needham, A Nicoll, C
Varela, P Vasconcelos, J Todd Webber, and A Wurz]
--
Communicated by:
ProMED-mail
<promed@promedmail.org>
See Also
Avian influenza, poultry vs migratory birds (36): Europe 20071128.3842Avian influenza, poultry vs migratory birds (35): H7 20070902.2887
Avian influenza, poultry vs migratory birds (34) 20070828.2815
Avian influenza, poultry vs migratory birds (33) 20070820.2719
Avian influenza, poultry vs migratory Birds (32): Europe 20070818.2700
Avian influenza, poultry vs migratory birds (31): Europe 20070817.2695
Avian influenza, poultry vs migratory birds (30): Germany 20070811.2612
Avian influenza, poultry vs migratory birds (29): France, swans 20070731.2469
Avian influenza, poultry vs migratory birds (28) 20070716.2279
Avian influenza, poultry vs migratory birds (27) 20070528.1712
Avian influenza, poultry vs migratory birds (26) 20070522.1645
Avian influenza, poultry vs migratory birds (25) 20070521.1613
Avian influenza, poultry vs migratory birds (24) 20070519.1596
Avian influenza, poultry vs migratory birds (23) 20070513.1531
Avian influenza, poultry vs migratory birds (22) 20070511.1512
Avian influenza, poultry vs migratory birds (21) 20070504.1453
Avian influenza, poultry vs migratory birds (20) 20070427.1379
Avian Influenza, poultry vs migratory birds (19) 20070424.1339
Avian influenza, poultry vs migratory birds (18) 20070422.1315
Avian influenza, poultry vs migratory birds (17): Kuwait, RFI 20070419.1285
Avian influenza, poultry vs migratory birds (16) 20070407.1172
Avian influenza, poultry vs migratory birds (15) 20070321.0993
Avian influenza, poultry vs migratory birds (14) 20070314.0905
Avian influenza, poultry vs migratory birds (13) 20070216.0587
Avian influenza, poultry vs migratory birds (12) 20070214.0556
Avian influenza, poultry vs migratory birds (11) 20070213.0539
Avian influenza, poultry vs migratory birds (10) 20070131.0394
Avian influenza, poultry vs migratory birds (09) 20070124.0323
Avian influenza, poultry vs migratory birds (08): RFI 20070120.0262
Avian influenza, poultry vs. migratory birds (07) 20070111.0135
Avian influenza, poultry vs migratory birds (06) 20070108.0082
Avian influenza, poultry vs migratory birds (05) 20070107.0071
Avian influenza, poultry vs migratory birds (04) 20070105.0049
Avian influenza, poultry vs migratory birds (03) 20070103.0024
Avian influenza, poultry vs migratory birds (02) 20070103.0017
Avian influenza, poultry vs migratory birds 20070102.0013
...................................mhj/mj/mpp
*##########################################################*
************************************************************
ProMED-mail makes every effort to verify the reports that
are posted, but the accuracy and completeness of the
information, and of any statements or opinions based
thereon, are not guaranteed. The reader assumes all risks in
using information posted or archived by ProMED-mail. ISID
and its associated service providers shall not be held
responsible for errors or omissions or held liable for any
damages incurred as a result of use or reliance upon posted
or archived material.
************************************************************
Become a ProMED-mail Premium Subscriber at
http://www.isid.org/ProMEDMail_Premium.shtml
************************************************************
Visit ProMED-mail's web site at <http://www.promedmail.org>.
Send all items for posting to: promed@promedmail.org
(NOT to an individual moderator). If you do not give your
full name and affiliation, it may not be posted. Send
commands to subscribe/unsubscribe, get archives, help,
etc. to: majordomo@promedmail.org. For assistance from a
human being send mail to: owner-promed@promedmail.org.
############################################################
############################################################