In vitro #neuraminidase inhibitory concentration (#IC50) of four neuraminidase inhibitors in the #Japanese 2017-18 #season: Comparison with the 2010-11 to 2016-17 seasons (J Infect Chemother., abstract)

[Source: US National Library of Medicine, full page: (LINK). Abstract, edited.]

J Infect Chemother. 2019 May 14. pii: S1341-321X(19)30099-6. doi: 10.1016/j.jiac.2019.04.007. [Epub ahead of print]

In vitro neuraminidase inhibitory concentration (IC50) of four neuraminidase inhibitors in the Japanese 2017-18 season: Comparison with the 2010-11 to 2016-17 seasons.

Ikematsu H1, Kawai N2, Chong Y3, Bando T2, Iwaki N2, Kashiwagi S2.

Author information: 1 Japan Physicians Association, Tokyo, Japan; Ricerca Clinica Co., Fukuoka, Japan. Electronic address: 2 Japan Physicians Association, Tokyo, Japan. 3 Medicine and Biosystemic Science, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.



To assess the extent of susceptibility to the four most commonly used neuraminidase inhibitors (NAIs) of the viruses epidemic in the 2017-18 Japanese influenza season, we measured the 50% inhibitory concentration (IC50) for influenza virus isolates from patients and compared them with the results from the 2010-11 to 2016-17 seasons. Viral isolation was done with specimens obtained prior to treatment, and the type and subtype was determined by RT-PCR using type- and subtype-specific primers. The IC50 was determined by a neuraminidase inhibition assay using a fluorescent substrate. A total of 237 virus isolates, 50 A(H1N1)pdm09, 92 A(H3N2), and 95 B were measured. No A(H1N1)pdm09 with highly reduced sensitivity for oseltamivir was found in the 2017-18 season. No isolates with highly reduced sensitivity to the four NAIs have been found for A(H3N2) or B from the 2010-11 to 2017-18 seasons. The geometric mean IC50s of the four NAIs were quite consistent during the eight studied seasons. These results indicate that the sensitivity to the four commonly used NAIs has been maintained.

Copyright © 2019 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

KEYWORDS: 50% inhibitory concentration; Influenza virus; Neuraminidase inhibitor; Resistance; Surveillance

PMID: 31101530 DOI: 10.1016/j.jiac.2019.04.007

Keywords: Antivirals; Drugs Resistance; Oseltamivir; Zanamivir; Peramivir; Laninamivir; Japan; Seasonal Influenza; H1N1pdm09; H3N2; Influenza B.



#Genetics and #pathogenicity of #H5N6 highly pathogenic #avian #influenza viruses isolated from #wildbirds and a #chicken in #Japan during winter 2017-2018 (Virology, abstract)

[Source: US National Library of Medicine, full page: (LINK). Abstract, edited.]

Virology. 2019 May 2;533:1-11. doi: 10.1016/j.virol.2019.04.011. [Epub ahead of print]

Genetics and pathogenicity of H5N6 highly pathogenic avian influenza viruses isolated from wild birds and a chicken in Japan during winter 2017-2018.

Mine J1, Uchida Y1, Nakayama M1, Tanikawa T1, Tsunekuni R1, Sharshov K2, Takemae N1, Sobolev I2, Shestpalov A2, Saito T3.

Author information: 1 Division of Transboundary Animal Disease, National Institute of Animal Health, National Agriculture and Food Research Organization (NARO), 3-1-5 Kannondai, Tsukuba, Ibaraki, 305-0856, Japan; Thailand-Japan Zoonotic Diseases Collaboration Center, Kasetklang, Chatuchak, Bangkok, 10900, Thailand. 2 Federal Research Center of Fundamental and Translational Medicine, Novosibirsk, Russia. 3 Division of Transboundary Animal Disease, National Institute of Animal Health, National Agriculture and Food Research Organization (NARO), 3-1-5 Kannondai, Tsukuba, Ibaraki, 305-0856, Japan; Thailand-Japan Zoonotic Diseases Collaboration Center, Kasetklang, Chatuchak, Bangkok, 10900, Thailand; United Graduate School of Veterinary Sciences, Gifu University, 1-1, Yanagito, Gifu, Gifu, 501-1112, Japan. Electronic address:



An H5N6 highly pathogenic avian influenza virus (HPAIV) outbreak occurred in poultry in Japan during January 2018, and H5N6 HPAIVs killed several wild birds in 3 prefectures during Winter 2017-2018. Time-measured phylogenetic analyses demonstrated that the Hemagglutinin (HA) and internal genes of these isolates were genetically similar to clade H5N8 HPAIVs in Europe during Winter 2016-2017, and Neuraminidase (NA) genes of the poultry and wild bird isolates were gained through distinct reassortments with AIVs that were estimated to have circulated possibly in Siberia during Summer 2017 and Summer 2016, respectively. Lethal infectious dose to chickens was similar between the poultry and wild-bird isolates. H5N6 HPAIVs during Winter 2017-2018 in Japan had higher 50% chicken lethal doses and lower transmission efficiency than the H5Nx HPAIVs that caused previous outbreaks in Japan, thus explaining in part why cases during the 2017-2018 outbreak were sporadic.

Copyright © 2019 Elsevier Inc. All rights reserved.

KEYWORDS: Animal RNA virus; H5N6 highly pathogenic avian influenza; Pathogenicity; Phylogeny

PMID: 31071540 DOI: 10.1016/j.virol.2019.04.011

Keywords: Avian Influenza; H5N6; H5N8; Wild Birds; Poultry; Japan.


#Outbreak of #aseptic #meningitis caused by #echovirus 30 in Kushiro, #Japan in 2017 (J Clin Virol., abstract)

[Source: Journal of Clinical Virology, full page: (LINK). Abstract, edited.]

Journal of Clinical Virology / Available online 6 May 2019 / In Press, Accepted Manuscript

Outbreak of aseptic meningitis caused by echovirus 30 in Kushiro, Japan in 2017

Yuji Maruo a, Masanori Nakanishi a, Yasuto Suzuki a, Yosuke Kaneshi a, Yukayo Terashita a, Masashi Narugami a, Michi Takahashi a, Sho Kato a, Ryota Suzuki a, Akiko Goto b, Masahiro Miyoshi b, Hideki Nagano b, Takahisa Sugisawa c, Motohiko Okano b

{a} Department of Pediatrics, Kushiro Red Cross Hospital, 21-14, Shinei-cho, Kushiro 085-8512, Japan; {b} Hokkaido Institute of Public Health, North 19 West 12, Kita-ku, Sapporo 060-0819, Japan; {c} Kushiro Center of Public Health, 4-22, Shiroyama 2, Kushiro 085-0826, Japan

Received 14 January 2019, Revised 23 April 2019, Accepted 5 May 2019, Available online 6 May 2019. DOI:



  • There was an outbreak of aseptic meningitis caused by E30 in Kushiro, Japan.
  • A neutrophil predominance was shown in CSF samples in many patients.
  • Phylogenetic analysis showed the same cluster.
  • Genotype of E30 was more closely related to strains in Europe than those in Japan.
  • Standard precautions are considered essential to prevent the spread of E30 infection.




Echovirus 30 (E30) is one of the most common causative agents for aseptic meningitis.


In the autumn of 2017, there was an outbreak caused by E30 in Kushiro, Hokkaido, Japan. The aim of this study was to characterize this outbreak.

Study design

Fifty-nine patients were admitted to the Department of Pediatrics, Kushiro Red Cross Hospital (KRCH) with clinical diagnosis of aseptic meningitis. Among those, 36 patients were finally diagnosed as E30-associated aseptic meningitis by the detection of viral RNA using reverse transcription-polymerase chain reaction (RT-PCR) and/or the evidence of more than four-fold rise in neutralizing antibody (NA) titers in the convalescent phase relative to those in the acute phase. We investigated these 36 confirmed cases.


The median age was 6 years (range: 6 months–14 years). The positive signs and symptoms were as follows: fever (100%), headache (94%), vomiting (92%), jolt accentuation (77%), neck stiffness (74%), Kernig sign (29%), and abdominal pain (28%). The median cerebrospinal fluid (CSF) white cell count, neutrophil count, and lymphocyte count were 222 /μL (range: 3–1,434 /μL), 144 /μL (range: 1–1,269 /μL), and 85 /μL (range: 2–354 /μL), respectively. Although the detected viral genes demonstrated same cluster, they were different from E30 strains observed in Japan between 2010 and 2014.


We mainly showed clinical and virological features of the E30-associated aseptic meningitis outbreak that occurred in Kushiro. To prevent further spread of E30 infection, continuous surveillance of enterovirus (EV) circulation and standard precautions are considered essential.

Abbreviations: E30 Echovirus 30 – EV enterovirus – KRCH Kushiro Red Cross Hospital –
RT-PCR reverse transcription-polymerase chain reaction – NA neutralizing antibody – CSF cerebrospinal fluid – CODEHOP consensus-degenerate hybrid oligonucleotide primer – VP viral protein – NT neutralization test – IgG immunoglobulin G – CRP C-reactive protein –

Keywords: aseptic meningitis – echovirus 30 – enterovirus – outbreak – children

© 2019 Elsevier B.V. All rights reserved.

Keywords: Enterovirus; Echovirus 30; Meningitis; Japan.


Comparing #Antimicrobial Susceptibilities among #Mycoplasma pneumoniae Isolated from #Pediatric Patients in #Japan between Two Recent #Epidemic Periods (Antimicrob Agents Chemother., abstract)

[Source: Antimicrobial Agents and Chemotherapy, full page: (LINK). Abstract, edited.]

Comparing Antimicrobial Susceptibilities among Mycoplasma pneumoniaeIsolated from Pediatric Patients in Japan between Two Recent Epidemic Periods

Tomohiro Oishi, Kento Takahashi, Shoko Wakabayashi, Yoshitaka Nakamura, Sahoko Ono, Mina Kono, Atsushi Kato, Aki Saito, Eisuke Kondo, Yuhei Tanaka, Hideto Teranishi, Hiroto Akaike,Takaaki Tanaka, Ippei Miyata, Satoko Ogita, Naoki Ohno, Takashi Nakano, Kazunobu Ouchi

DOI: 10.1128/AAC.02517-18



We compared the antimicrobial susceptibility of Mycoplasma pneumoniae isolated from pediatric patients in Japan in 2011–2012 and 2015–2016 when epidemics occurred. The antimicrobial activity of macrolides and tetracyclines against M. pneumoniae tended to be restored in 2015–2016. There was no change in the antimicrobial activity of quinolones against M. pneumoniae.

Copyright © 2019 Oishi et al. This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International license.

Keywords: Antibiotics; Drugs Resistance; Quinolones; Macrolides; Tetracyclines; Mycoplasma pneumoniae; Japan.


#Clonal expansion and spread of the #ceftriaxone-resistant #Neisseria gonorrhoeae strain FC428, identified in #Japan in 2015, and closely related isolates (J Antimicrob Chemother., abstract)

[Source: Journal of Antimicrobial Chemotherapy, full page: (LINK). Abstract, edited.]

Clonal expansion and spread of the ceftriaxone-resistant Neisseria gonorrhoeae strain FC428, identified in Japan in 2015, and closely related isolates

Kenichi Lee, Shu-Ichi Nakayama, Kayo Osawa, Hiroyuki Yoshida, Soichi Arakawa, Kei-Ichi Furubayashi, Hiroshi Kameoka, Ken Shimuta, Takuya Kawahata, Magnus Unemo, Makoto Ohnishi

Journal of Antimicrobial Chemotherapy, dkz129,

Published: 19 April 2019




Ceftriaxone resistance in Neisseria gonorrhoeae is a major public health concern globally because a high-dose (1 g) injection of ceftriaxone is the only remaining option for empirical monotherapy of gonorrhoea. The ceftriaxone-resistant gonococcal strain FC428, cultured in Osaka in 2015, is suspected to have spread nationally and internationally. We describe the complete finished genomes of FC428 and two closely related isolates from Osaka in 2015, and examine the genomic epidemiology of these isolates plus three ceftriaxone-resistant gonococcal isolates from Osaka and Hyogo in 2016–17 and four ceftriaxone-resistant gonococcal isolates cultured in 2017 in Australia, Canada and Denmark.


During 2015–17, we identified six ceftriaxone-resistant gonococcal isolates through our surveillance systems in Kyoto, Osaka and Hyogo. Antimicrobial susceptibility testing (six antimicrobials) was performed using Etest. Complete whole-genome sequences of the first three isolates (FC428, FC460 and FC498) from 2015 were obtained using PacBio RS II and Illumina MiSeq sequencing. The three complete genome sequences and draft genome sequences of the three additional Japanese (sequenced with Illumina MiSeq) and four international ceftriaxone-resistant isolates were compared.


Detailed genomic analysis suggested that the Japanese isolates (FC428, FC460, FC498, KU16054, KM383 and KU17039) and the four international MLST ST1903 isolates from Australia, Canada and Denmark formed four linked subclades.


Using detailed genomic analysis, we describe the clonal expansion of the ceftriaxone-resistant N. gonorrhoeae strain FC428, initially identified in 2015 in Japan, and closely related isolates. FC428 and its close relatives show some genomic diversity, suggesting multiple genetic subclades are already spreading internationally.


© The Author(s) 2019. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For permissions, please email:

This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (

Keywords: Antibiotics; Drugs Resistance; Ceftriaxone; Neisseria gonorrhoeae; Japan.


Novel #Sequence Type in #Bacillus cereus Strains Associated with #Nosocomial #Infections and #Bacteremia, #Japan (Emerg Infect Dis., abstract)

[Source: US Centers for Disease Control and Prevention (CDC), Emerging Infectious Diseases Journal, full page: (LINK). Abstract, edited.]

Volume 25, Number 5—May 2019 / CME ACTIVITY – Research

Novel Sequence Type in Bacillus cereus Strains Associated with Nosocomial Infections and Bacteremia, Japan

Reiko Akamatsu, Masato Suzuki, Keiji Okinaka, Teppei Sasahara, Kunikazu Yamane, Satowa Suzuki, Daisuke Fujikura1, Yoshikazu Furuta, Naomi Ohnishi2, Minoru Esaki, Keigo Shibayama, and Hideaki Higashi

Author affiliations: Hokkaido University, Sapporo, Japan (R. Akamatsu, D. Fujikura, Y. Furuta, N. Ohnishi, H. Higashi); National Institute of Infectious Diseases, Tokyo, Japan (M. Suzuki, S. Suzuki, K. Shibayama); National Cancer Center Hospital, Tokyo (K. Okinaka, M. Esaki); Jichi Medical University, Tochigi, Japan (T. Sasahara); Yonago Medical Center, Tottori, Japan (K. Yamane)



Bacillus cereus is associated with foodborne illnesses characterized by vomiting and diarrhea. Although some B. cereus strains that cause severe extraintestinal infections and nosocomial infections are recognized as serious public health threats in healthcare settings, the genetic backgrounds of B. cereus strains causing such infections remain unknown. By conducting pulsed-field gel electrophoresis and multilocus sequence typing, we found that a novel sequence type (ST), newly registered as ST1420, was the dominant ST isolated from the cases of nosocomial infections that occurred in 3 locations in Japan in 2006, 2013, and 2016. Phylogenetic analysis showed that ST1420 strains belonged to the Cereus III lineage, which is much closer to the Anthracis lineage than to other Cereus lineages. Our results suggest that ST1420 is a prevalent ST in B. cereus strains that have caused recent nosocomial infections in Japan.

Keywords: Bacillus cereus; Nosocomial Outbreaks; Bacteremia; Japan.


#Influenza #H3N2 exhibiting reduced susceptibility to #baloxavir due to a #PA I38T substitution detected from a hospitalised child without prior treatment, #Japan, Jan. ’19 (Euro Surveill., abstract)

[Source: Eurosurveillance, full page: (LINK). Abstract, edited.]

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

Emi Takashita1, Chiharu Kawakami2, Rie Ogawa1, Hiroko Morita1, Seiichiro Fujisaki1, Masayuki Shirakura1, Hideka Miura1, Kazuya Nakamura1, Noriko Kishida1, Tomoko Kuwahara1, Akira Ota3, Hayato Togashi3, Ayako Saito4, Keiko Mitamura5, Takashi Abe6, Masataka Ichikawa7, Masahiko Yamazaki8, Shinji Watanabe1, Takato Odagiri1

Affiliations: 1 Influenza Virus Research Center, National Institute of Infectious Diseases, Tokyo, Japan; 2 Yokohama City Institute of Public Health, Kanagawa, Japan; 3 Saiseikai Yokohamashi Nanbu Hospital, Kanagawa, Japan; 4 Saito Children’s Clinic, Kanagawa, Japan; 5 Eiju General Hospital, Tokyo, Japan; 6 Abe Children’s Clinic, Kanagawa, Japan; 7 Ichikawa Children’s Clinic, Kanagawa, Japan; 8 Zama Children’s Clinic, Kanagawa, Japan

Correspondence: Takato

Citation style for this article: Takashita Emi, Kawakami Chiharu, Ogawa Rie, Morita Hiroko, Fujisaki Seiichiro, Shirakura Masayuki, Miura Hideka, Nakamura Kazuya, Kishida Noriko, Kuwahara Tomoko, Ota Akira, Togashi Hayato, Saito Ayako, Mitamura Keiko, Abe Takashi, Ichikawa Masataka, Yamazaki Masahiko, Watanabe Shinji, Odagiri Takato. 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. Euro Surveill. 2019;24(12):pii=1900170.

Received: 06 Mar 2019;   Accepted: 21 Mar 2019



In January 2019, two influenza A(H3N2) viruses carrying an I38T substitution in the polymerase acidic subunit (PA), which confers reduced susceptibility to baloxavir, were detected from epidemiologically unrelated hospitalised children in Japan. The viruses exhibited reduced susceptibility to baloxavir but were susceptible to neuraminidase inhibitors. Only one of the two children had been treated with baloxavir. An epidemiological analysis suggests possible transmission of the PA I38T mutant A(H3N2) virus among humans.

© This work is licensed under a Creative Commons Attribution 4.0 International License.

Keywords: Antivirals; Drugs Resistance; Baloxavir; Seasonal Influenza; H3N2; Japan.