COVID-19 vaccine effectiveness against severe COVID-19 requiring oxygen therapy, invasive mechanical ventilation, and death in Japan: A multicenter case-control study (MOTIVATE study)
Year: 2023
Type: article
Study design: Observational Study
Abstract: INTRODUCTION: Since the SARS-CoV-2 Omicron variant became dominant, assessing COVID-19 vaccine effectiveness (VE) against severe disease using hospitalization as an outcome became more challenging due to incidental infections via admission screening and variable admission criteria, resulting in a wide range of estimates. To address this, the World Health Organization (WHO) guidance recommends the use of outcomes that are more specific to severe pneumonia such as oxygen use and mechanical ventilation. METHODS: A case-control study was conducted in 24 hospitals in Japan for the Delta-dominant period (August-November 2021; "Delta") and early Omicron (BA.1/BA.2)-dominant period (January-June 2022; "Omicron"). Detailed chart review/interviews were conducted in January-May 2023. VE was measured using various outcomes including disease requiring oxygen therapy, disease requiring invasive mechanical ventilation (IMV), death, outcome restricting to "true" severe COVID-19 (where oxygen requirement is due to COVID-19 rather than another condition(s)), and progression from oxygen use to IMV or death among COVID-19 patients. RESULTS: The analysis included 2125 individuals with respiratory failure (1608 cases [75.7%]; 99.2% of vaccinees received mRNA vaccines). During Delta, 2 doses provided high protection for up to 6 months (oxygen requirement: 95.2% [95% CI:88.7-98.0%] [restricted to "true" severe COVID-19: 95.5% {89.3-98.1%}]; IMV: 99.6% [97.3-99.9%]; fatal: 98.6% [92.3-99.7%]). During Omicron, 3 doses provided high protection for up to 6 months (oxygen requirement: 85.5% [68.8-93.3%] ["true" severe COVID-19: 88.1% {73.6-94.7%}]; IMV: 97.9% [85.9-99.7%]; fatal: 99.6% [95.2-99.97]). There was a trend towards higher VE for more severe and specific outcomes. CONCLUSION: Multiple outcomes pointed towards high protection of 2 doses during Delta and 3 doses during Omicron. These results demonstrate the importance of using severe and specific outcomes to accurately measure VE against severe COVID-19, as recommended in WHO guidance in settings of intense transmission as seen during Omicron.
Source: Vaccine
Authors: Takeshi Arashiro, Maki Miwa, Hidenori Nakagawa, Junpei Takamatsu, Kunihiro Oba, Satoshi Fujimi, Hitoshi Kikuchi, Takamasa Iwasawa, Fumiko Kanbe, Keisuke Oyama, Masayuki Kanai, Yoshitaka Ogata, Takanori Asakura, Takahiro Asami, Keiko Mizuno, Manabu Sugita, Torahiko Jinta, Yusuke Nishida, Hideaki Kato, Kazuaki Atagi, Taiki Higaki, Yoshio Nakano, Takeya Tsutsumi, Kent Doi, Shu Okugawa, Akihiro Ueda, Akira Nakamura, Toru Yoshida, Kaoru Shimada-Sammori, Keiki Shimizu, Yasuo Fujita, Yasumi Okochi, Kentaro Tochitani, Asuka Nakanishi, Hiroshi Rinka, Daisuke Taniyama, Asase Yamaguchi, Toshio Uchikura, Maiko Matsunaga, Hiromi Aono, Masanari Hamaguchi, Kentaro Motoda, Sohei Nakayama, Kei Yamamoto, Hideaki Oka, Katsushi Tanaka, Takeshi Inoue, Mieko Kobayashi, Shigeki Fujitani, Maki Tsukahara, Saki Takeda, Ashley Stucky, Tadaki Suzuki, Chris Smith, Martin Hibberd, Koya Ariyoshi, Yuji Fujino, Yuzo Arima, Shinhiro Takeda, Satoru Hashimoto, Motoi Suzuki
Institutions: National Institute of Infectious Diseases, London School of Hygiene & Tropical Medicine, Nagasaki University, Tokyo Metropolitan Hiroo Hospital, Osaka City General Hospital, Kansai Rosai Hospital, Showa General Hospital, Osaka Prefectural Medical Center, Sagamihara Kyodo Hospital, Yokosuka General Hospital Uwamachi, Ageo Central General Hospital, Tokyo Metropolitan Police Hospital, Yao Tokushukai General Hospital, Kitasato Institute Hospital, Kitasato University, Sanokousei General Hospital, Juntendo University Nerima Hospital, St. Luke's International Hospital, Social Insurance Saitama Chuo Hospital, Saitama Medical Center, Saitama Medical University, Yokohama City University Hospital, Nara Prefecture General Medical Center, Asahi General Hospital, Kinan Hospital, University of Tokyo Hospital, Japanese Red Cross Medical Center, St. Marianna University School of Medicine, Akita Red Cross Hospital, Tokyo Metropolitan Tama Medical Center, Japan Community Healthcare Organization, Tokyo Yamate Medical Center, Kyoto City Hospital, The University of Osaka
Language: English
Subfield: Infectious Diseases
Field: Medicine
Domain: Health Sciences
Open Access status: hybrid
Estimated APC paid: $3,350
OpenAlex ID: W4389903141