著者
Nobumasa Okumura Shinya Tsuzuki Sho Saito Tomoya Saito Satoshi Takasago Masayuki Hojo Noriko Iwamoto Norio Ohmagari
出版者
National Center for Global Health and Medicine
雑誌
Global Health & Medicine (ISSN:24349186)
巻号頁・発行日
pp.2021.01124, (Released:2021-12-30)
参考文献数
11
被引用文献数
6

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant has spread rapidly worldwide. We report the clinical characteristics and threshold cycle (Ct) values of the first 11 patients infected with the SARS-CoV-2 Omicron variant in Japan. All patients were younger returnees from abroad; 10 patients had received two doses of vaccine. Estimated Ct values for the 11 patients were 6.0 (95% confidence interval [CI] 4.2-7.3) days for > 30, 10.6 (95% CI 9.5-11.9) days for > 35, 15.1 (95% CI 13.6-17.6) days for > 40, and 19.7 (95% CI 17.3-23.7)days for > 45. Our results provide important insights for indicators of infection control.
著者
Eisuke Adachi Amato Otani Hiroshi Yotsuyanagi Masayuki Saijo Tomoya Saito
出版者
National Center for Global Health and Medicine
雑誌
Global Health & Medicine (ISSN:24349186)
巻号頁・発行日
pp.2023.01089, (Released:2023-11-27)
参考文献数
12

At the beginning of the mpox (disease caused by monkey pox) epidemic, there was no platform in Japan to provide appropriate information on emerging and re-emerging infectious diseases (EIDs), and the number of accesses to bioterrorism-related information sites increased rapidly. Even though the interest in mpox was much smaller than in coronavirus infectious disease, emerged in late 2019 (COVID-19), the increase in the number of views were much greater than during the COVID-19 epidemic. This may not be because mpox is bioterrorism-related as an analog of smallpox, but rather because there were no other websites providing information on mpox. For future crisis management, there should be a platform to provide information on possible epidemics of EIDs from normal times in Japan.
著者
Tsuyoshi Sekizuka Kentaro Itokawa Masumichi Saito Michitsugu Shimatani Shutoku Matsuyama Hideki Hasegawa Tomoya Saito Makoto Kuroda
出版者
National Institute of Infectious Diseases, Japanese Journal of Infectious Diseases Editorial Committee
雑誌
Japanese Journal of Infectious Diseases (ISSN:13446304)
巻号頁・発行日
pp.JJID.2021.844, (Released:2022-02-28)
参考文献数
12
被引用文献数
21

Prominent genomic recombination has been observed between the Delta and Alpha variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) isolated from clinical specimens in Japan. Interestingly, the recombination variant detected in this study carries a spike protein identical to the one in the domestic Delta variant, thereby suggesting that further risks would not be concerned with infectivity and immune escape. The recombinant has been classified as XC lineage in the PANGOLIN database. It is necessary to intensively study such marked genetic variations and characterize the emerging variants after careful verification of their lineage and clade assignment.
著者
Nobuhiro Takemae Yen Hai Doan Fumitaka Momose Tomoya Saito Tsutomu Kageyama
出版者
National Institute of Infectious Diseases, Japanese Journal of Infectious Diseases Editorial Committee
雑誌
Japanese Journal of Infectious Diseases (ISSN:13446304)
巻号頁・発行日
pp.JJID.2022.007, (Released:2022-01-31)
参考文献数
10
被引用文献数
10

The World Health Organization (WHO) designated Omicron (B.1.1.529 lineage) of SARS-CoV-2 as a new variant of concern (VOC) on 26th of November 2021. The risk to public health conferred by the Omicron variant is still not completely clear, although its numerous gene mutations raise concern about its potential for increased transmissibility and immune escape. In this study, we describe our development of two single nucleotide polymorphism (SNP) genotyping assays targeting the G339D or T547K mutation of the spike protein for screening of the Omicron variant. A specificity test revealed that the two assays successfully discriminated the Omicron variant from the Delta variant and Alpha variant each with one nucleotide mismatch. In addition, a sensitivity test showed that the G339D and T547K assays detected at least 2.60 and 3.36 RNA copies of the Omicron variant, respectively, and 1.59 RNA copies of the Delta variant. These results demonstrated that both assays could be useful for detecting and discriminating the Omicron variant from other strains. In addition, because of the rapid and unpredictable evolution of SARS-CoV-2, combining our assays with previously developed assays for detecting other mutations may lead to a more accurate diagnosis system.