Research Findings from Antiviral Resistance Surveillance

2025

• Global update on the susceptibilities of influenza viruses to neuraminidase inhibitors and the cap-dependent endonuclease inhibitor baloxavir, 2020-2023.
  Hussain S, Meijer A, Govorkova EA, Dapat C, Gubareva LV, Barr I, Brown SK, Daniels RS, Fujisaki S, Galiano M, Huang W, Kondor RJ, Lackenby A, Lewis N, Lo J, Nguyen HT, Patel MC, Pereyaslov D, Rattigan A, Samaan M, Wang D, Webby RJ, Yen HL, Zhang W, Takashita E. Antiviral Res. 2025 Jun 24:106217.
• Impact of the polymerase acidic protein E199K substitution in influenza A viruses on baloxavir susceptibility.
  Takashita E, Yasui Y, Ikegaya A, Saka K, Maeshiro N, Morita H, Nagata S, Fujisaki S, Miura H, Kishida N, Nakamura K, Shirakura M, Watanabe S, Hasegawa H; Influenza Virus Surveillance Group of Japan. Antiviral Res. 2025 May 3;239:106173.
• Influenza A(H1N1)pdm09 Virus with Reduced Susceptibility to Baloxavir, Japan, 2024.
  Takashita E, Morita H, Nagata S, Fujisaki S, Miura H, Ikeda T, Komabayashi K, Sasaki M, Matoba Y, Takahashi T, Ogawa N, Mizuta K, Ito S, Kishida N, Nakamura K, Shirakura M, Watanabe S, Hasegawa H. Emerg Infect Dis. 2025 May;31(5):1019-1023.

2024

• An outbreak of influenza A(H1N1)pdm09 antigenic variants exhibiting cross-resistance to oseltamivir and peramivir in an elementary school in Japan, September 2024.
  Takashita E, Shimizu K, Usuku S, Senda R, Okubo I, Morita H, Nagata S, Fujisaki S, Miura H, Kishida N, Nakamura K, Shirakura M, Ichikawa M, Matsuzaki Y, Watanabe S, Takahashi Y, Hasegawa H. Euro Surveill. 2024 Dec;29(50):2400786.

2023

• A community cluster of influenza A(H3N2) virus infection with reduced susceptibility to baloxavir due to a PA E199G substitution in Japan, February to March 2023.
  Takashita E, Fujisaki S, Morita H, Nagata S, Miura H, Matsuura Y, Yamamoto S, Chiba S, Inoue Y, Minami I, Yoshikawa S, Yamazaki S, Kishida N, Nakamura K, Shirakura M, Watanabe S, Hasegawa H. Euro Surveill. 2023 Sep;28(39):2300501.

2022

• Global update on the susceptibilities of human influenza viruses to neuraminidase inhibitors and the cap-dependent endonuclease inhibitor baloxavir, 2018-2020.
  Govorkova EA, Takashita E, Daniels RS, Fujisaki S, Presser LD, Patel MC, Huang W, Lackenby A, Nguyen HT, Pereyaslov D, Rattigan A, Brown SK, Samaan M, Subbarao K, Wong S, Wang D, Webby RJ, Yen HL, Zhang W, Meijer A, Gubareva LV. Antiviral Res. 2022 Apr;200:105281.
• Antiviral Susceptibilities of Avian Influenza A(H5), A(H7), and A(H9) Viruses Isolated in Japan.
  Takashita E, Morita H, Nagata S, Shirakura M, Fujisaki S, Miura H, Takayama I, Arita T, Suzuki Y, Yamaoka M, Tanikawa T, Tsunekuni R, Mine J, Sakuma S, Uchida Y, Shibata A, Iwanaka M, Kishida N, Nakamura K, Kageyama T, Watanabe S, Hasegawa H; Influenza Virus Surveillance Group of Japan. Jpn J Infect Dis. 2022 Jul 22;75(4):398-402.

2020

• In Vitro Characterization of Multidrug-Resistant Influenza A(H1N1)pdm09 Viruses Carrying a Dual Neuraminidase Mutation Isolated from Immunocompromised Patients.
  Takashita E, Fujisaki S, Yokoyama M, Shirakura M, Morita H, Nakamura K, Kishida N, Kuwahara T, 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. Pathogens. 2020 Sep 2;9(9):725.
• Influenza A(H1N1)pdm09 virus exhibiting reduced susceptibility to baloxavir due to a PA E23K substitution detected from a child without baloxavir treatment.
  Takashita E, Abe T, Morita H, Nagata S, Fujisaki S, Miura H, Shirakura M, Kishida N, Nakamura K, Kuwahara T, Mitamura K, Ichikawa M, Yamazaki M, Watanabe S, Hasegawa H; Influenza Virus Surveillance Group of Japan. Antiviral Res. 2020 Aug;180:104828.
• Detection of a Peramivir-Resistant Influenza B/Yamagata-Lineage Virus Imported from Indonesia in Aichi, Japan, March 2019.
  Takashita E, Yasui Y, Nagata S, Morita H, Fujisaki S, Miura H, Shirakura M, Kishida N, Nakamura K, Kuwahara T, Sugawara H, Sato A, Akimoto M, Kaido T, Watanabe S, Hasegawa H; Influenza Virus Surveillance Group of Japan. Jpn J Infect Dis. 2020 Sep 24;73(5):386-390.
• Rapid detection of an I38T amino acid substitution in influenza polymerase acidic subunit associated with reduced susceptibility to baloxavir marboxil.
  Nakauchi M, Takashita E, Fujisaki S, Shirakura M, Ogawa R, Morita H, Miura H, Saito S, Watanabe S, Odagiri T, Kageyama T. Influenza Other Respir Viruses. 2020 Jul;14(4):436-443.
• Global update on the susceptibilities of human influenza viruses to neuraminidase inhibitors and the cap-dependent endonuclease inhibitor baloxavir, 2017-2018.
  Takashita E, Daniels RS, Fujisaki S, Gregory V, Gubareva LV, Huang W, Hurt AC, Lackenby A, Nguyen HT, Pereyaslov D, Roe M, Samaan M, Subbarao K, Tse H, Wang D, Yen HL, Zhang W, Meijer A. Antiviral Res. 2020 Mar;175:104718.

2019

• Human-to-Human Transmission of Influenza A(H3N2) Virus with Reduced Susceptibility to Baloxavir, Japan, February 2019.
  Takashita E, Ichikawa M, Morita H, Ogawa R, Fujisaki S, Shirakura M, Miura H, Nakamura K, Kishida N, Kuwahara T, Sugawara H, Sato A, Akimoto M, Mitamura K, Abe T, Yamazaki M, Watanabe S, Hasegawa H, Odagiri T. Emerg Infect Dis. 2019 Nov;25(11):2108-2111.
• Influenza A(H3N2) virus exhibiting reduced susceptibility to baloxavir due to a polymerase acidic subunit I38T substitution detected from a hospitalised child without prior baloxavir treatment, Japan, January 2019.
  Takashita E, Kawakami C, Ogawa R, Morita H, Fujisaki S, Shirakura M, Miura H, Nakamura K, Kishida N, Kuwahara T, Ota A, Togashi H, Saito A, Mitamura K, Abe T, Ichikawa M, Yamazaki M, Watanabe S, Odagiri T. Euro Surveill. 2019 Mar;24(12):1900170.
• Detection of influenza A(H3N2) viruses exhibiting reduced susceptibility to the novel cap-dependent endonuclease inhibitor baloxavir in Japan, December 2018.
  Takashita E, Kawakami C, Morita H, Ogawa R, Fujisaki S, Shirakura M, Miura H, Nakamura K, Kishida N, Kuwahara T, Mitamura K, Abe T, Ichikawa M, Yamazaki M, Watanabe S, Odagiri T; Influenza Virus Surveillance Group of Japan. Euro Surveill. 2019 Jan;24(3):1800698.

2018

• Susceptibility of Influenza Viruses to the Novel Cap-Dependent Endonuclease Inhibitor Baloxavir Marboxil.
  Takashita E, Morita H, Ogawa R, Nakamura K, Fujisaki S, Shirakura M, Kuwahara T, Kishida N, Watanabe S, Odagiri T.Front Microbiol. 2018 Dec 6;9:3026.
• Global update on the susceptibility of human influenza viruses to neuraminidase inhibitors and status of novel antivirals, 2016-2017.
  Lackenby A, Besselaar TG, Daniels RS, Fry A, Gregory V, Gubareva LV, Huang W, Hurt AC, Leang SK, Lee RTC, Lo J, Lollis L, Maurer-Stroh S, Odagiri T, Pereyaslov D, Takashita E, Wang D, Zhang W, Meijer A. Antiviral Res. 2018 Sep;157:38-46.

2017

• Global update on the susceptibility of human influenza viruses to neuraminidase inhibitors, 2015-2016.
  Gubareva LV, Besselaar TG, Daniels RS, Fry A, Gregory V, Huang W, Hurt AC, Jorquera PA, Lackenby A, Leang SK, Lo J, Pereyaslov D, Rebelo-de-Andrade H, Siqueira MM, Takashita E, Odagiri T, Wang D, Zhang W, Meijer A. Antiviral Res. 2017 Oct;146:12-20.

2016

• Influenza A(H1N1)pdm09 virus exhibiting enhanced cross-resistance to oseltamivir and peramivir due to a dual H275Y/G147R substitution, Japan, March 2016.
  Takashita E, Fujisaki S, Shirakura M, Nakamura K, Kishida N, Kuwahara T, Shimazu Y, Shimomura T, Watanabe S, Odagiri T; Influenza Virus Surveillance Group of Japan. Euro Surveill. 2016 Jun 16;21(24).
• Antiviral susceptibility of influenza viruses isolated from patients pre- and post-administration of favipiravir.
  Takashita E, Ejima M, Ogawa R, Fujisaki S, Neumann G, Furuta Y, Kawaoka Y, Tashiro M, Odagiri T. Antiviral Res. 2016 Aug;132:170-7.
• Global update on the susceptibility of human influenza viruses to neuraminidase inhibitors, 2014-2015.
  Hurt AC, Besselaar TG, Daniels RS, Ermetal B, Fry A, Gubareva L, Huang W, Lackenby A, Lee RT, Lo J, Maurer-Stroh S, Nguyen HT, Pereyaslov D, Rebelo-de-Andrade H, Siqueira MM, Takashita E, Tashiro M, Tilmanis D, Wang D, Zhang W, Meijer A. Antiviral Res. 2016 Aug;132:178-85.
• Characterization of an A (H1N1)pdm09 Virus Imported from India in March 2015.
  Takashita E, Fujisaki S, Shirakura M, Nakamura K, Kishida N, Kuwahara T, Ohmiya S, Sato K, Ito H, Chiba F, Nishimura H, Shindo S, Watanabe S, Odagiri T; Influenza Virus Surveillance Group of Japan. Jpn J Infect Dis. 2016;69(1):83-6.

2015

• Global update on the susceptibility of human influenza viruses to neuraminidase inhibitors, 2013-2014.
  Takashita E, Meijer A, Lackenby A, Gubareva L, Rebelo-de-Andrade H, Besselaar T, Fry A, Gregory V, Leang SK, Huang W, Lo J, Pereyaslov D, Siqueira MM, Wang D, Mak GC, Zhang W, Daniels RS, Hurt AC, Tashiro M. Antiviral Res. 2015 May;117:27-38.
• Characterization of a large cluster of influenza A(H1N1)pdm09 viruses cross-resistant to oseltamivir and peramivir during the 2013-2014 influenza season in Japan.
  Takashita E, Kiso M, Fujisaki S, Yokoyama M, Nakamura K, Shirakura M, Sato H, Odagiri T, Kawaoka Y, Tashiro M. Antimicrob Agents Chemother. 2015 May;59(5):2607-17.

2014

• Global update on the susceptibility of human influenza viruses to neuraminidase inhibitors, 2012-2013.
  Meijer A, Rebelo-de-Andrade H, Correia V, Besselaar T, Drager-Dayal R, Fry A, Gregory V, Gubareva L, Kageyama T, Lackenby A, Lo J, Odagiri T, Pereyaslov D, Siqueira MM, Takashita E, Tashiro M, Wang D, Wong S, Zhang W, Daniels RS, Hurt AC. Antiviral Res. 2014 Oct;110:31-41.
• A community cluster of influenza A(H1N1)pdm09 virus exhibiting cross-resistance to oseltamivir and peramivir in Japan, November to December 2013.
  Takashita E, Ejima M, Itoh R, Miura M, Ohnishi A, Nishimura H, Odagiri T, Tashiro M. Euro Surveill. 2014 Jan 9;19(1):20666.

2013

• Characterization of neuraminidase inhibitor-resistant influenza A(H1N1)pdm09 viruses isolated in four seasons during pandemic and post-pandemic periods in Japan.
  Takashita E, Fujisaki S, Kishida N, Xu H, Imai M, Tashiro M, Odagiri T; Influenza Virus Surveillance Group of Japan. Influenza Other Respir Viruses. 2013 Nov;7(6):1390-9.