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-------- Original Message
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| Subject:
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[Fwd: IVPHC: Geographic Spread of Novel Influeza
A/H1N1 by Migratory Birds] |
| Date:
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Wed, 06 May 2009 09:35:25 -0700 |
| From:
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"Stephen M. Apatow" <s.m.apatow@pathobiologics.org> |
| To:
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ivphc.wg@pathobiologics.org |
6 May 2009
IDIN:
Pathobiologics
International: Biodefense Threat Analysis
& Communication Center
Subject: Pandemic Influenza:
Contingency Planning Discussion
Now that genetic analysis has confirmed the presence
of H5N1 genetic components in the Novel Influenza A/H1N1
strain, the subject
of geographic spread via migratory birds comes back into focus.
During 2005, a significant source of international
spread of Avian influenza A (H5N1) (H5N1) in birds became apparent for the
first time. Scientists are increasingly convinced that at least some migratory
waterfowl are now carrying the H5N1 virus in its highly pathogenic form, sometimes
over long distances, and introducing the virus to poultry flocks in areas
that lie along their migratory routes. Scientific studies comparing viruses
from different outbreaks in birds have found that viruses from the most recently
affected countries, all of which lie along migratory routes, are almost identical
to viruses recovered from dead migratory birds at Qinghai Lake. Viruses from
Turkey’s first two human cases, which were fatal, were also virtually identical
to viruses from Qinghai Lake. -- Avian Influenza, hopkinsmedicine.org.
How long is the virus viable outside of the host in the environment
- i.e., how long does it remain contagious to birds or humans?
HPAI viruses can remain viable for long periods of time at
moderate temperatures in the environment, and can survive indefinitely in
frozen material. In poultry houses, live virus has been found more than 100
days after the facility was depopulated. One gram of contaminated manure
can contain enough virus to infect 1 million birds. -- Frequently
Asked Questions on Avian Influenza, originally printed in The Wildlife
Rehabilitator, Volume 6, Issue 1, Winter 2006.
Global Patterns of Influenza A Virus in Wild Birds: Science
21 April 2006: Vol. 312. no. 5772, pp. 384 - 388, DOI: 10.1126/science.1122438.
Fig. 1. Migratory flyways of wild bird populations.
A world map with the main general migratory flyways of wild bird populations
is shown (adapted from information collected and analyzed by Wetlands International).
(A) Black dots indicate the locations of historical and current influenza
virus surveillance sites from which data have been used in this manuscript.
These global migration flyways are simplifications, and there are situations
where populations behave differently from the common patterns. Migration patterns
of Mallard (Anas platyrhynchos) (B) and Garganey (Anas querquedula)
in Eurasia and Africa and Blue-winged Teal (Anas discors) in the Americas
(C) (right and left parts of the map, respectively) are provided.
Yellow color indicates breeding areas in which species are absent during
winter, green indicates areas in which species are present around the year,
and blue indicates areas in which species are only present in winter and
do not breed. Arrows indicate the seasonal migration patterns. Click
for larger image.
Related:
Stephen M. Apatow
Founder, Director of Research and Development
Pathobiologics
International
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