ProMED: H5N1 almost forgotten, but not gone

[alert]

This is NOT a report of an outbreak, but rather a summary of the past few years.

http://www.promedmail.org/pls/otn/f?p=2400:1001:38587976131353::NO::F2400_P1001_BACK_PAGE,F2400_P1001_PUB_MAIL_ID:1000,80971

Archive Number 20100118.0200
Published Date 18-JAN-2010
Subject PRO/AH/EDR> Avian influenza, human (03): update


AVIAN INFLUENZA, HUMAN (03): UPDATE
***********************************
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 15 Jan 2010
Source: Science, ScienceInsider [edited]
<http://blogs.sciencemag.org/scienceinsider/2010/01/h5n1-forgotten.html>


H5N1 forgotten (almost), but not gone
-------------------------------------
While the world's flu fighters have concentrated on countering the H1N1
swine flu pandemic, avian influenza H5N1 has quietly continued to take its
toll on both poultry and humans. Last year, 17 countries, stretching from
Cote d'Ivoire and Germany to China and Japan, reported outbreaks of H5N1 in
domestic poultry and wild birds; and the World Health Organization, which
still says H5N1 poses a pandemic threat, recorded 72 human cases, 32 of
them fatal [in 2009]. The brunt of the outbreak, entering its 8th year, is
still in China and the developing countries of South East Asia. [In fact in
2009 39 of the 72 confirmed human cases were recorded in Egypt. - Mod.CP]
[In the year 2009] Indonesia alone accounted for 19 of the 32 H5N1 [human]
deaths; Viet Nam, for 5 and China for 4. But there are glimmers of progress.

The number of human deaths has been dropping since peaking at 79 in 2006.
And fewer countries reported outbreaks in 2009 than in 2008 [5 in 2009, 6
in 2008]. Countries are refining responses to outbreaks, as was in evidence
at the Asian Partnership on Emerging Infectious Diseases Researchmeeting in
Kunming, China, from 13 to 16 Jan 2010.

Partnership researchers from Cambodia, China, Indonesia, Laos, Thailand,
and Viet Nam compared notes on the effectiveness of control measures.
Scientists reported that carefully targeted culling can be just as
effective as widespread culling, and less disruptive. Others reported that
reducing risk among those keeping backyard poultry has to be a
community-wide effort, since changing the practices of individual farmers
has proven difficult.

In particular, Witthawat Wiriyarat, a veterinarian and virologist at
Mahidol University in Bangkok told ScienceInsider that a 3 year old
regional surveillance network is making progress in sorting out the role of
wild birds. Some waterfowl initially thought to be spreading the virus,
such as the Asian openbill stork, are now known to quickly succumb to H5N1
infection, Wiriyarat says. But passerine species, or perching birds, are
apparently carrying the virus without ill effects, says Fumin Lei, of the
Chinese Academy of Sciences' Institute of Zoology in Beijing. He adds that
there is a high correlation of outbreaks in poultry and passerine movements.

Wiriyarat says it is still unclear what is sustaining the outbreak, whether
there is a natural reservoir for H5N1, and how the virus is passed between
domestic and wild birds. But while that research continues, the most
effective way to reduce the amount of virus in circulation is to control
outbreaks in poultry, he says.

[byline: Dennis Normile]

--
communicated by:
ProMED-mail rapporteur Mary Marshall

[For a complete record of the H5N1 avian influenza virus outbreak from 2003
up to the present interested readers should consult the WHO table of
confirmed human cases of avian influenza A/(H1N1) as of 30 Dec 2009 at
<http://www.who.int/csr/disease/avian_influenza/country/cases_table_2009_12_30/en/index.html>
and the WHO timeline at
<http://www.who.int/csr/disease/avian_influenza/Timeline_10_01_04.pdf>.

In total, as of 30 Dec 2009 there have been 467 confirmed human cases and
282 deaths. Of the 5 countries reporting H5N1 cases in 2009 mortality was
least in Egypt with 4 deaths among 39 cases and highest in Indonesia with
19 deaths among 20 cases, suggesting that surveillance and treatment
procedures may be improving. - Mod.CP

A timeline of the H5N1 panzootic evolvement since its initial detection in
2003, when Hong Kong reported 2 outbreaks in domestic poultry and 3
outbreaks in wildlife, updatedJan 2010, is available on the OIE website at
<http://www.oie.int/eng/info_ev/en_AI_factoids_H5N1_Timeline.htm>; links to
other useful sources are included.

62 countries reported H5N1 avian influenza in domestic poultry/wildlife
2003-2010. During 2009, the disease was officially reported from 17
countries. - Mod.AS]

[see also:
2009
---
Avian influenza, human (11): China, WHO Update 20090119.0240
2006
---
Avian influenza, human (123): Thailand, vaccine update 20060818.2315
Avian influenza, human - Eurasia (50): Iraq, WHO update 20060208.0411
Avian influenza, human - Eurasia (04): Turkey: WHO update 20060107.0052
2005
---
Avian influenza, human - East Asia (161): WHO travel update 20051106.3249
Avian influenza, human - East Asia (142): CDC update 20051008.2941
Avian influenza, human - East Asia (117): WHO Update 20050818.2423
Avian influenza, human - East Asia (105): CDC update 20050724.2144
Avian influenza, human - East Asia (79): WHO update 20050519.1376
Avian influenza, human - East Asia (09): CDC update 20050116.0144
2004
---
Avian influenza, human - East Asia (52): update 20041004.2738
Avian influenza, human - East Asia (35): Update 20040717.1939]

.......................cp/ejp/sh