tetano
Editor, Senior Moderator
Influenza Other Respir Viruses. 2020 Jan 19. doi: 10.1111/irv.12713. [Epub ahead of print] [h=1]Antigenic variants of influenza B viruses isolated in Japan during the 2017-2018 and 2018-2019 influenza seasons.[/h]
Kato-Miyashita S[SUP]1[/SUP], Sakai-Tagawa Y[SUP]1[/SUP], Yamashita M[SUP]1[/SUP], Iwatsuki-Horimoto K[SUP]1[/SUP], Ito M[SUP]1[/SUP], Tokita A[SUP]2,[/SUP][SUP]3[/SUP], Hagiwara H[SUP]3,[/SUP][SUP]4[/SUP], Izumida N[SUP]3,[/SUP][SUP]5[/SUP], Nishino T[SUP]3,[/SUP][SUP]6[/SUP], Wada N[SUP]3,[/SUP][SUP]7[/SUP], Koga M[SUP]8[/SUP], Adachi E[SUP]9[/SUP], Jubishi D[SUP]1,[/SUP][SUP]10[/SUP], Yotsuyanagi H[SUP]9[/SUP], Kawaoka Y[SUP]1,[/SUP][SUP]11,[/SUP][SUP]12[/SUP], Imai M[SUP]1[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] [h=4]BACKGROUND:[/h] Here, we genetically and antigenically analyzed influenza B viruses (IBVs) isolated in Japan during the 2017-2018 and 2018-2019 influenza seasons.
[h=4]METHODS:[/h] A total of 68 IBVs (61 B/Yamagata/16/88-like [B/Yamagata]-lineage and 7 B/Victoria/2/87-like [B/Victoria]-lineage) were antigenically and genetically characterized by using hemagglutination inhibition (HI) assays and phylogenetic analysis, respectively. The susceptibility of IBVs to neuraminidase (NA) inhibitors was assessed by using a fluorescence-based NA inhibition assay.
[h=4]RESULTS:[/h] All 61 B/Yamagata-lineage isolates were genetically closely related to B/Phuket/3073/2013, the vaccine strain for these two seasons. Eleven B/Yamagata-lineage isolates tested were antigenically similar to B/Phuket/3073/2013 by the HI test. Seven B/Victoria-lineage isolates were genetically closely related to B/Texas/02/2013, the WHO-recommended vaccine strain for the 2017-2018 season; however, they were antigenically distinct from B/Texas/02/2013 with an eightfold or 16-fold difference in HI titer. Of these 7 isolates, 4 possessed a two-amino-acid deletion at positions 162 and 163 in hemagglutinin (HA) and the other 3 had a three-amino-acid deletion at positions 162-164 in HA. Importantly, the variants with the three-amino-acid deletion appeared to be antigenically different from the B/Colorado/06/2017 virus with the two-amino-acid deletion, the vaccine strain for the 2018-2019 season with a fourfold or eightfold difference in HI titer. One B/Yamagata-lineage isolate carrying a G407S mutation in its NA showed a marked reduction in susceptibility to zanamivir, peramivir, and laninamivir.
[h=4]CONCLUSIONS:[/h] These results highlight the need for continued monitoring for the prevalence of the antigenic variant with the three-amino-acid deletion and the variant with reduced NA inhibitor susceptibility.
? 2020 The Authors. Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.
[h=4]KEYWORDS:[/h] Japan; antigenicity; hemagglutinin; influenza B virus; neuraminidase inhibitors
PMID: 31955521 DOI: 10.1111/irv.12713
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Kato-Miyashita S[SUP]1[/SUP], Sakai-Tagawa Y[SUP]1[/SUP], Yamashita M[SUP]1[/SUP], Iwatsuki-Horimoto K[SUP]1[/SUP], Ito M[SUP]1[/SUP], Tokita A[SUP]2,[/SUP][SUP]3[/SUP], Hagiwara H[SUP]3,[/SUP][SUP]4[/SUP], Izumida N[SUP]3,[/SUP][SUP]5[/SUP], Nishino T[SUP]3,[/SUP][SUP]6[/SUP], Wada N[SUP]3,[/SUP][SUP]7[/SUP], Koga M[SUP]8[/SUP], Adachi E[SUP]9[/SUP], Jubishi D[SUP]1,[/SUP][SUP]10[/SUP], Yotsuyanagi H[SUP]9[/SUP], Kawaoka Y[SUP]1,[/SUP][SUP]11,[/SUP][SUP]12[/SUP], Imai M[SUP]1[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] [h=4]BACKGROUND:[/h] Here, we genetically and antigenically analyzed influenza B viruses (IBVs) isolated in Japan during the 2017-2018 and 2018-2019 influenza seasons.
[h=4]METHODS:[/h] A total of 68 IBVs (61 B/Yamagata/16/88-like [B/Yamagata]-lineage and 7 B/Victoria/2/87-like [B/Victoria]-lineage) were antigenically and genetically characterized by using hemagglutination inhibition (HI) assays and phylogenetic analysis, respectively. The susceptibility of IBVs to neuraminidase (NA) inhibitors was assessed by using a fluorescence-based NA inhibition assay.
[h=4]RESULTS:[/h] All 61 B/Yamagata-lineage isolates were genetically closely related to B/Phuket/3073/2013, the vaccine strain for these two seasons. Eleven B/Yamagata-lineage isolates tested were antigenically similar to B/Phuket/3073/2013 by the HI test. Seven B/Victoria-lineage isolates were genetically closely related to B/Texas/02/2013, the WHO-recommended vaccine strain for the 2017-2018 season; however, they were antigenically distinct from B/Texas/02/2013 with an eightfold or 16-fold difference in HI titer. Of these 7 isolates, 4 possessed a two-amino-acid deletion at positions 162 and 163 in hemagglutinin (HA) and the other 3 had a three-amino-acid deletion at positions 162-164 in HA. Importantly, the variants with the three-amino-acid deletion appeared to be antigenically different from the B/Colorado/06/2017 virus with the two-amino-acid deletion, the vaccine strain for the 2018-2019 season with a fourfold or eightfold difference in HI titer. One B/Yamagata-lineage isolate carrying a G407S mutation in its NA showed a marked reduction in susceptibility to zanamivir, peramivir, and laninamivir.
[h=4]CONCLUSIONS:[/h] These results highlight the need for continued monitoring for the prevalence of the antigenic variant with the three-amino-acid deletion and the variant with reduced NA inhibitor susceptibility.
? 2020 The Authors. Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.
[h=4]KEYWORDS:[/h] Japan; antigenicity; hemagglutinin; influenza B virus; neuraminidase inhibitors
PMID: 31955521 DOI: 10.1111/irv.12713
Free full text