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**gsgs** · July 31, 2014, 09:38 AM

Re: H7n9

Infection with Possible Precursor of Avian Influenza A(H7N9) Virus

Table 1 - Infection with Possible Precursor of Avian Influenza A(H7N9) Virus in a Child, China, 2013 - Volume 20, Number 8—August 2014 - Emerging Infectious Diseases journal - CDC

http://wwwnc.cdc.gov/eid/article/20/8/14-0325-t1

avian influenza virus, viruses, A(H7N9), phylogenetics, evolution, genome sequence, pediatric, China, adaption, zoonoses, respiratory infections, fomite

A/Shanghai/JS01/2013/04/03,H7N9

to me it looks like it's the domestic ducks in China where the virus
evolves and developes new strains, dangerous for humans.
Wild mallards as well as chickens can contribute new segments that
are then reassorted in domestic ducks and are maintained and can
further evolve and develope mutations and deletions/insertions.
The improved new strains then go to chickens who are often
in proximity of domestic ducks in China.

the decisive moment in the emergence of H7N9 seems to have been the
deletion in NA in early 2013. That new strain had some new characteristics
which made it dangerous to humans.
These deletions are rare in nature, somehow harder to achieve than single
mutations, but we could easily test some other such deletions in the lab
so to gain the function of other circulating strains ...

---------------------------------------------------------

Influenza A virus (A/duck/Hunan/S4111/2011(H9N2)) polymerase PB2 (PB2) - Nucleotide - NCBI

http://www.ncbi.nlm.nih.gov/nuccore/CY146657

A/duck/Hunan/S4111/2011(H9N2

Deng,G., Tan,D., Shi,J., Cui,P., Jiang,Y., Liu,L., Tian,G.,
Kawaoka,Y., Li,C. and Chen,H.
TITLE Complex reassortment of multiple subtypes of avian influenza
viruses in domestic ducks at the Dongting Lake region of China
---------------------------------------------------------

Code:

segment 4, HA:
   0    0 1683   49 >A/Index/H7N9-China/2013/03/,H7N9
--------------------------------------------------------
  53    9 1683   11 >KF609511,A/Shanghai/JS01/2013,2013/04/03,China,H7N9,Human

 219   37 1683  140 >KF259041,A/pigeon/Wenzhou/559/2013,2013//,China,H7N7,Avian
 231   39 1683    7 >KF258995,A/duck/Fujian/6390/2010,2010//,China,H7N3,Avian
 231   39 1683    8 >KF258963,A/duck/Fujian/6388/2010,2010//,China,H7N3,Avian
 231   39 1683   10 >KF258962,A/duck/Fujian/6380/2010,2010//,China,H7N3,Avian
 231   39 1683  141 >KF259040,A/duck/Wenzhou/47/2013,2013//,China,H7N7,Avian
 237   40 1683    9 >KF258994,A/duck/Fujian/6326/2010,2010//,China,H7N3,Avian
 237   40 1683  142 >KF259039,A/duck/Wenzhou/775/2013,2013//,China,H7N2,Avian
 237   40 1683  143 >KF259009,A/duck/Wenzhou/771/2013,2013//,China,H7N3,Avian
 243   41 1683  144 >KF258958,A/goose/Guangdong/7472/2012,2012//,China,H7N7,Avian
 272   42 1541  181 >KF297292,A/silkie chicken/Wenzhou/804b/2013,2013//,China,H7N7,Avian

 409   69 1683    3 >JQ906575,A/duck/Zhejiang/11/2011,2011/06/,China,H7N3,Avian

 463   78 1683  309 >KF259000,A/wild duck/Jiangxi/10179/2005,2005//,China,H7N3,Avian

 482   81 1680  294 >FJ750875,A/wild bird feces/Korea/HDR22/2006,2006//,South Korea,H7N7,Avian
 484   80 1650  324 >EU158102,A/duck/Jiangxi/1786/03,2003//,China,H7N7,Avian

 510   86 1683  314 >AB473543,A/duck/Mongolia/867/2002,2002//,Mongolia,H7N1,Avian

 558   94 1683  328 >AB269695,A/duck/Taiwan/4201/99,1999//,Taiwan,H7N7,Avian

Code:

segment 4
   0    0 1413   24 >KF259728,A/northern shoveler/Hong Kong/MPL133/2010,2010//,Hong Kong,H2N9,Avian
----------------------------------------
  28    4 1413   21 >KF259698,A/duck/Jiangxi/21714/2011,2011//,China,H11N9,Avian
  28    4 1413   23 >KF259726,A/northern shoveler/Hong Kong/MPL961/2011,2011//,Hong Kong,H2N9,Avian
  35    5 1413   11 >KC609801,A/wild duck/Korea/SH19-47/2010,2010/12/,South Korea,H7N9,Avian
  35    5 1413   20 >KC609799,A/wild duck/Korea/SH19-27/2010,2010/12/,South Korea,H7N9,Avian
  36    5 1355   15 >KC609803,A/wild duck/Korea/MHC35-41/2011,2011/03/,South Korea,H7N9,Avian
  37    5 1345   13 >KC609800,A/wild duck/Korea/SH19-44/2010,2010/12/,South Korea,H7N9,Avian
  37    5 1348   12 >KC609798,A/wild duck/Korea/SH19-50/2010,2010/01/,South Korea,H7N9,Avian
  39    5 1253   14 >KC609804,A/wild duck/Korea/MHC35-25/2011,2011/03/,South Korea,H7N9,Avian
  55    3  541   42 >KF028388,A/Shanghai/5058T/2013,2013/04/19,China,H7N9,Human
  56    8 1413   22 >KF259703,A/wild waterfowl/Hong Kong/MPP1311/2013,2013//,Hong Kong,H2N9,Avian
  61    8 1309   19 >KC609808,A/wild duck/Korea/CSM42-1/2011,2011/03/,South Korea,H7N9,Avian
  63    9 1413   25 >KF006416,A/chicken/Jiangsu/RD5/2013,2013/03/,China,H10N9,Avian
  63    9 1413   26 >KF609513,A/Shanghai/JS01/2013,2013/04/03,China,H7N9,Human
  66    9 1354   16 >KC609806,A/wild duck/Korea/MHC39-26/2011,2011/03/,South Korea,H7N9,Avian
  72   10 1383   17 >KC609805,A/wild duck/Korea/MHC39-13/2011,2011/03/,South Korea,H7N9,Avian
  84   12 1413    2 >CY146614,A/duck/Hunan/S1607/2012,2012/03/24,China,H11N9,Avian
  84   12 1413    6 >CY146638,A/duck/Hunan/S4013/2011,2011/11/09,China,H11N9,Avian
  84   12 1413    7 >CY146686,A/duck/Hunan/S4137/2011,2011/11/11,China,H11N9,Avian
  84   12 1413   10 >KF259695,A/duck/Guizhou/1078/2011,2011//,China,H11N9,Avian
  92   13 1398   27 >CY147014,A/chicken/Shanghai/S1358/2013,2013/04/03,China,H7N9,Avian
  92   13 1398   43 >CY147038,A/chicken/Zhejiang/SD007/2013,2013/04/22,China,H7N9,Avian
  92   13 1398  108 >KC896765,A/environment/Nanjing/2913/2013,2013/03/29,China,H7N9,Environment
  92   13 1413    3 >CY146734,A/environment/Hunan/S11511/2012,2012/03/24,China,H4N9,Environment
  93   13 1392   18 >KC609809,A/wild duck/Korea/CSM42-34/2011,2011/03/,South Korea,H7N9,Avian

 100   14 1398  162 >A/Index/H7N9-China/2013/03/,H7N9

Code:

segment 6, NA
   0    0 1398  162 >A/Index/H7N9-China/2013/03/,H7N9
---------------------------------------------------------
  50    7 1398   26 >KF609513,A/Shanghai/JS01/2013,2013/04/03,China,H7N9,Human

  78   11 1398   61 >KF226107,A/Jiangsu/2/2013,2013/04/20,China,H7N9,Human
 100   14 1398   24 >KF259728,A/northern shoveler/Hong Kong/MPL133/2010,2010//,Hong Kong,H2N9,Avian
 121   17 1398   25 >KF006416,A/chicken/Jiangsu/RD5/2013,2013/03/,China,H10N9,Avian
 128   18 1398   21 >KF259698,A/duck/Jiangxi/21714/2011,2011//,China,H11N9,Avian
 128   18 1398   23 >KF259726,A/northern shoveler/Hong Kong/MPL961/2011,2011//,Hong Kong,H2N9,Avian
 135   19 1398   11 >KC609801,A/wild duck/Korea/SH19-47/2010,2010/12/,South Korea,H7N9,Avian
 135   19 1398   20 >KC609799,A/wild duck/Korea/SH19-27/2010,2010/12/,South Korea,H7N9,Avian
 141   19 1340   15 >KC609803,A/wild duck/Korea/MHC35-41/2011,2011/03/,South Korea,H7N9,Avian
 142   19 1330   13 >KC609800,A/wild duck/Korea/SH19-44/2010,2010/12/,South Korea,H7N9,Avian
 142   19 1333   12 >KC609798,A/wild duck/Korea/SH19-50/2010,2010/01/,South Korea,H7N9,Avian

Attached Files

**gsgs** · December 29, 2014, 10:55 PM

Just a moment...

http://www.pnas.org/content/early/2014/12/25/1422456112.abstract

Evolution of the H9N2 influenza genotype that facilitated the genesis of the novel H7N9 virus

感谢您的浏览！ - 新华网

http://news.xinhuanet.com/english/health/2014-12/30/c_127345176.htm

> the genetic diversity of H9N2 viruses fell sharply in 2009 and from 2010 to 2013,
> an H9N2 virus emerged as the predominant subtype thanks to its genetic makeup
> that allowed it to flourish despite widespread vaccination of chickens against H9N2 viruses.
> Liu: "The dominant H9N2 virus had changed antigenicity and improved adaptability in chickens,"
> That may be one reason for its widespread outbreak from 2010 to 2013.
> The emergence of this dominant H9N2 virus was the first step in the genesis of the H7N9
> viruses because it greatly increased the likelihood of reassortment between H9N2 and
> other flu subtypes. Reassortment refers to the tendency of flu viruses to swap genes.

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