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Update on Influenza Virus Surveillance Findings in 2008/09 Season in Northern Hemisphere Who Collaborating Center for Reference and Research on Influenza at Center for Influenza Virus Research, National Institute of Infectious Diseases, Tokyo, Japan Takato Odagiri, Ph.D.
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Weekly report of virus isolation/detection in 2008-09 season By NIID By CDC Pandemic A/H1N1 viruses
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A(H1N1) viruses September 2008-January 2009
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H1N1, Sept 2008 – Jan 2009
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H1N1 antigenic analysis By NIID
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H1N1 antigenic analysis By CDC
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Summary of antigenic analysis of A/H1N1 in four WHO CCs A/Br/59/07-like low-reactors (≥ 8-f) CDC (Oct-) 179 [100%] 0 [0%] NIID (Oct-) 72 [95%] 4 [5%] NIMR (Oct-) 62 [87%] 9 [13%] VIDRL (Oct-) 119 [97.5%] 3 [2.5%] Total 432 [96%] 16 [4%]
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March-July 2009
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By CDC
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By NIMR
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Antigenic characterization of AH1N1 viruses isolated after March By NIID By CDC
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Number of oseltamivir resistance viruses isolated in Japan ( Oct 2008-May 2009 ) By NIID
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H1N1 viruses - Summary Oct 2008-Feb 2009 Influenza A(H1N1) viruses predominated in many Asian and North American countries The majority of viruses were antigenically closely related to A/Brisbane/59/2007 by HI analysis Phylogenetically the majority of H1N1 viruses grouped into the A/Brisbane/59/2007 clade (2B) based on their HA gene. Recent 2B viruses share H275Y indicative of resistance to oseltamivir. They were antigenically similar to osel-sensitive viruses. Recent viruses from China fall within the A/Hong Kong/2652/2006 clade (2C) and these viruses were similar antigenically to clade 2B viruses. Clade 2C viruses are sensitive to oseltamivir and resistant to amantadine/rimantadine Mar - July 2009 The features of viruses were similar to those observed earlier in 2009. Majority of recent A(H1N1) viruses were antigenically closely related to A/Brisbane/59/2007 and formed clade 2B sharing H275Y. In the few clade 2C viruses, dual resistance to oseltamivir and amantadine/rimantadine were detected.
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A(H3N2) viruses September 2008-January 2009
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H3N2, Sept 2008 – Jan 2009
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By NIID
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By NIMR
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A/Brisbane/10/07-like low-reactors (≥ 8-f) CDC (Oct-) 45 [90%] 5 [10%] NIID (Oct-) 32 [56%]25 [44%] NIMR (Oct-)160 [90%]18 [10%]* VIDRL (Oct-)145 [93%]11 [ 7%] Total382 [87%]59 [13%] H3 low reactors in HI assays in WHOCCs * 0% by virus neutralization
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Vaccine virus
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March-July 2009
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By NIMR
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By NIID
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Vaccine virus
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By Cambridge Univ.
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H3N2 viruses - Summary Oct 2008-Feb 2009 H3N2 viruses co-circulated with H1N1 and B viruses in many countries Majority were antigenically similar to A/Brisbane/10/07 and A/Uruguay/716/07 by HI tests with turkey RBCs or guinea pig RBCs. The ‘low reactors’ were antigenically indistinguishable from vaccine viruses by Neutralization tests. HA and NA sequences fairly homogeneous and fell within the A/Brisbane/10/07 clade M2 sequences possessed S31N mutation, indicative of amantadine resistance Sensitive to oseltamivir and zanamivir Mar - July 2009 Majority were antigenically similar to vaccine viruses. An increasing number of H3N2 isolates have been shown to be antigenically distinct from vaccine viruses and related to A/Hawaii/7/09, A/HK/1985/09 and A/Perth/16/09. The majority of HA sequences of those viruses formed a separate clade characterized by aa subsitutions E62K, N144K, K158N and N18K. They retained resistance to amantadine/rimantadine and were sensitive to oseltamivir and zanamivir.
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B viruses September 2008-January 2009
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B, Sept 2008 – Jan 2009
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Numbers of 2 lineages of B viruses detected in GISN since week 40 2008 B-Victoria lineage B-Yamagata lineage
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HI reactions of influenza type B viruses By NIID
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HI reactions of influenza type B viruses B/Victoria-lineage By NIMR
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HI reactions of influenza type B viruses B/Yamagata lineage By NIMR
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Victoria Yamagata CDC (Oct-)71 [60%]48 [40%] low reactors (77%) (23%) NIID (Oct-)18 [40%] 27[60%] Low reactors (94%) (67%) NIMR 17 [44%] 22[56%] Low reactors (76%) (14%) VIDRL (Oct-)340 [67%]167 [33%] Low reactors (94%) (62%) Total446 [63%] 264 [37%] Low reactors (91%) (51%) B low reactors in HI assays in WHOCCs
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10 nucleotides B/Brisbane/60/2008-like Evolutionary Relationships Among Influenza B (Victoria Lineage) HA Genes B/Malaysia/2506/2004 K165N Chinese clade By Melbourne C.
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Evolutionary Relationships Among Influenza B (Yamagata Lineage) HA Genes 10 nucleotides By Melbourne C.
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March-July 2009
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By NIMR HI reactions of influenza type B viruses B/Victoria-lineage
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By CDC
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By Cambridge Univ.
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B/Victoria-lineage HA By NIID Vaccine virus Chinese viruses
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By CDC B/Yamagata-lineage HA Vaccine virus
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Summary for influenza B viruses Oct 2008-Feb 2009 Influenza B viruses circulated in many countries however regional outbreaks were limited. Viruses of both B/Victoria/2/87 and B/Yamagata/16/88 lineages continued to co-circulate in many countries B/Victoria-lineage viruses predominated in most countries and were mostly antigenically closely related to B/Brisbane/60/2008. Viruses mainly from China fell into a separate phylogenetic clade B/Yamagata-lineage viruses were antigenically closely related to B/Florida/4/2006 & B/Brisbane/3/2007 vaccine viruses. Three phylogenetic clades were apparent but were antigenically indistinguishable. Mar - July 2009 B/Victoria-lineage viruses predominated and were mostly antigenically closely related to vaccine strain B/Brisbane/60/2008. Many viruses isolated in China were closely related to B/Fujian Gulou/1272/08 and B/Hubei-Songzi/51/08. B/Yamagata-lineage viruses were antigenically closely related to B/Florida/4/2006 and mostly fell into their HA sequences of the B/Bagladesh/3333/07 clade.
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WHO Collaborating Centers ( US-CDC, NIMR, Melbourne ) Cambridge University NICs (China-CDC, Korea-CDC, NHL-Myanmar, NCLE-Lao PDR, NIH-Mongolia and other NICs of WHO GISN) Taiwan-CDC Local PHLs in Japan Acknowledgement
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