- 著者
- Takahiro Sanada Tomoko Honda Fumihiko Yasui Kenzaburo Yamaji Tsubasa Munakata Naoki Yamamoto Makoto Kurano Yusuke Matsumoto Risa Kohno Sakiko Toyama Yoshiro Kishi Takuro Horibe Yudai Kaneko Mayumi Kakegawa Kazushige Fukui Takeshi Kawamura Wang Daming Chungen Qian Fuzhen Xia Fan He Syudo Yamasaki Atsushi Nishida Takayuki Harada Masahiko Higa Yuko Tokunaga Asako Takagi Masanari Itokawa Tatsuhiko Kodama Michinori Kohara
- 出版者
- Japan Epidemiological Association
- 雑誌
- Journal of Epidemiology (ISSN:09175040)
- 巻号頁・発行日
- pp.JE20210324, (Released:2021-11-13)
- 参考文献数
- 26
- 被引用文献数
- 18
Background: Tokyo, the capital of Japan, is a densely populated city of >13 million people and thus at high risk of epidemic severe acute respiratory coronavirus 2 (SARS-CoV-2) infection. A serologic survey of anti–SARS-CoV-2 IgG would provide valuable data for assessing the city’s SARS-CoV-2 infection status. This cross-sectional study therefore estimated the anti–SARS-CoV-2 IgG seroprevalence in Tokyo.Methods: Leftover serum of 23,234 hospital visitors was tested for antibodies against SARS-CoV-2 using an iFlash 3000 chemiluminescence immunoassay analyzer (Shenzhen YHLO Biotech) with an iFlash–SARS-CoV-2 IgG kit (YHLO) and iFlash–SARS-CoV-2 IgG-S1 kit (YHLO). Serum samples with a positive result (≥10 AU/mL) in either of these assays were considered seropositive for anti–SARS-CoV-2 IgG. Participants were randomly selected from patients visiting 14 Tokyo hospitals between September 1, 2020, and March 31, 2021. No participants were diagnosed with coronavirus disease 2019 (COVID-19), and none exhibited COVID-19–related symptoms at the time of blood collection.Results: The overall anti–SARS-CoV-2 IgG seroprevalence among all participants was 1.83% (95% confidence interval [CI]: 1.66%-2.01%). The seroprevalence in March 2021, the most recent month of this study, was 2.70% (95% CI: 2.16%-3.34%). After adjusting for population age, sex, and region, the estimated seroprevalence in Tokyo was 3.40%, indicating that 470,778 individuals had a history of SARS-CoV-2 infection.Conclusions: The estimated number of individuals in Tokyo with a history of SARS-CoV-2 infection was 3.9-fold higher than the number of confirmed cases. Our study enhances understanding of the SARS-CoV-2 epidemic in Tokyo.
- 著者
- Takahiro Sanada Tomoko Honda Fumihiko Yasui Kenzaburo Yamaji Tsubasa Munakata Naoki Yamamoto Makoto Kurano Yusuke Matsumoto Risa Kohno Sakiko Toyama Yoshiro Kishi Takuro Horibe Yudai Kaneko Mayumi Kakegawa Kazushige Fukui Takeshi Kawamura Wang Daming Chungen Qian Fuzhen Xia Fan He Syudo Yamasaki Atsushi Nishida Takayuki Harada Masahiko Higa Yuko Tokunaga Asako Takagi Masanari Itokawa Tatsuhiko Kodama Michinori Kohara
- 出版者
- Japan Epidemiological Association
- 雑誌
- Journal of Epidemiology (ISSN:09175040)
- 巻号頁・発行日
- vol.32, no.2, pp.105-111, 2022-02-05 (Released:2022-02-05)
- 参考文献数
- 26
- 被引用文献数
- 4 18
Background: Tokyo, the capital of Japan, is a densely populated city of >13 million people, so the population is at high risk of epidemic severe acute respiratory coronavirus 2 (SARS-CoV-2) infection. A serologic survey of anti–SARS-CoV-2 IgG would provide valuable data for assessing the city’s SARS-CoV-2 infection status. Therefore, this cross-sectional study estimated the anti–SARS-CoV-2 IgG seroprevalence in Tokyo.Methods: Leftover serum of 23,234 hospital visitors was tested for antibodies against SARS-CoV-2 using an iFlash 3000 chemiluminescence immunoassay analyzer (Shenzhen YHLO Biotech, Shenzhen, China) with an iFlash–SARS-CoV-2 IgG kit (YHLO) and iFlash–SARS-CoV-2 IgG-S1 kit (YHLO). Serum samples with a positive result (≥10 AU/mL) in either of these assays were considered seropositive for anti–SARS-CoV-2 IgG. Participants were randomly selected from patients visiting 14 Tokyo hospitals between September 1, 2020 and March 31, 2021. No participants were diagnosed with coronavirus disease 2019 (COVID-19), and none exhibited COVID-19-related symptoms at the time of blood collection.Results: The overall anti–SARS-CoV-2 IgG seroprevalence among all participants was 1.83% (95% confidence interval [CI], 1.66–2.01%). The seroprevalence in March 2021, the most recent month of this study, was 2.70% (95% CI, 2.16–3.34%). After adjusting for population age, sex, and region, the estimated seroprevalence in Tokyo was 3.40%, indicating that 470,778 individuals had a history of SARS-CoV-2 infection.Conclusions: The estimated number of individuals in Tokyo with a history of SARS-CoV-2 infection was 3.9-fold higher than the number of confirmed cases. Our study enhances understanding of the SARS-CoV-2 epidemic in Tokyo.
- 著者
- Takahiro Sanada Michinori Kohara
- 出版者
- Japan Epidemiological Association
- 雑誌
- Journal of Epidemiology (ISSN:09175040)
- 巻号頁・発行日
- vol.33, no.2, pp.109, 2023-02-05 (Released:2023-02-05)
- 参考文献数
- 5
- 被引用文献数
- 1
- 著者
- Kyoko TSUKIYAMA-KOHARA Michinori KOHARA
- 出版者
- Japanese Association for Laboratory Animal Science
- 雑誌
- Experimental Animals (ISSN:13411357)
- 巻号頁・発行日
- vol.63, no.4, pp.367-374, 2014 (Released:2014-10-30)
- 参考文献数
- 41
- 被引用文献数
- 24 23
Tupaias, or tree shrews, are small mammals that are similar in appearance to squirrels. The morphological and behavioral characteristics of the group have been extensively characterized, and despite previously being classified as primates, recent studies have placed the group in its own family, the Tupaiidae. Genomic analysis has revealed that the genus Tupaia is closer to humans than it is to rodents. In addition, tupaias are susceptible to hepatitis B virus and hepatitis C virus. The only other experimental animal that has been demonstrated to be sensitive to both of these viruses is the chimpanzee, but restrictions on animal testing have meant that experiments using chimpanzees have become almost impossible. Consequently, the development of the tupaia for use as an animal infection model could become a powerful tool for hepatitis virus research and in preclinical studies on drug development.