In vitro characterization of multidrug-resistant influenza A(H1N1)pdm09 viruses carrying a dual amino acid substitution associated with reduced susceptibility to neuraminidase inhibitors

Takashita, E.; Fujisaki, S.; Yokoyama, M.; Shirakura, M.; Nakamura, K.; Kuwahara, T.; Kishida, N.; Sato, H.; Doi, I.; Sato, Y.; Takao, S.; Shimazu, Y.; Shimomura, T.; Ito, T.; Watanabe, S.; Odagiri, T.; The Influenza Virus Surveillance Group of Japan,

doi:10.1101/334185

bioRxiv · 10.1101/334185

In vitro characterization of multidrug-resistant influenza A(H1N1)pdm09 viruses carrying a dual amino acid substitution associated with reduced susceptibility to neuraminidase inhibitors

Takashita, E.·Fujisaki, S.·Yokoyama, M.·Shirakura, M.·Nakamura, K.·Kuwahara, T.·Kishida, N.·Sato, H.·Doi, I.·Sato, Y.·Takao, S.·Shimazu, Y.·Shimomura, T.·Ito, T.·Watanabe, S.·Odagiri, T.·The Influenza Virus Surveillance Group of Japan,

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Abstract

We detected influenza A(H1N1)pdm09 viruses carrying dual H275Y/I223R, H275Y/I223K, or H275Y/G147R substitutions in their neuraminidase protein, respectively. These viruses showed cross-resistance to oseltamivir and peramivir and reduced susceptibility to zanamivir. The H275Y/G147R virus retained its replication capability at least in vitro, but the H275Y/I223R and H275Y/I223K viruses did not.

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Takashita, E., Fujisaki, S., Yokoyama, M., Shirakura, M., Nakamura, K., Kuwahara, T., Kishida, N., Sato, H., Doi, I., Sato, Y., Takao, S., Shimazu, Y., Shimomura, T., Ito, T., Watanabe, S., Odagiri, T., The Influenza Virus Surveillance Group of Japan,. 2018-05-30. In vitro characterization of multidrug-resistant influenza A(H1N1)pdm09 viruses carrying a dual amino acid substitution associated with reduced susceptibility to neuraminidase inhibitors. https://doi.org/10.1101/334185

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