著者

Wataru Mimura Chieko Ishiguro Junko Terada-Hirashima Nobuaki Matsunaga Shuntaro Sato Yurika Kawazoe Megumi Maeda Fumiko Murata Haruhisa Fukuda

出版者

Japan Epidemiological Association

雑誌

Journal of Epidemiology (ISSN:09175040)

巻号頁・発行日

pp.JE20230106, (Released:2023-09-23)

参考文献数

33

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Background: We evaluated the effectiveness of the BNT162b2 vaccine against infection, symptomatic infection, and hospitalization in older people during the Delta-predominant period (July 1 to September 30, 2021).Methods: We performed a population-based cohort study in an older adult population aged ≥65 years using data from the Vaccine Effectiveness, Networking, and Universal Safety Study conducted from January 1, 2019, to September 30, 2021, in Japan. We matched BNT162b2 vaccinated and unvaccinated individuals in a 1:1 ratio on the date of vaccination of the vaccinated individual. We evaluated the effectiveness of the vaccine against infection, symptomatic infection, and COVID-19-related hospitalization by comparing the vaccinated and unvaccinated groups. We estimated the risk ratio and risk difference using the Kaplan–Meier method with inverse probability weighting. The vaccine effectiveness was calculated as (1 − risk ratio) × 100%.Results: The study included 203,574 matched pairs aged ≥65 years. At 7 days after the second dose, the vaccine effectiveness (95% confidence interval) of BNT162b2 against infection, symptomatic infection, and hospitalization was 78.1% (65.2 to 87.8%), 79.1% (64.6 to 88.9%), and 93.5% (83.7 to 100%), respectively.Conclusions: BNT162b2 was highly effective against infection, symptomatic infection, and hospitalization in Japan's older adult population aged ≥65 years during the Delta-predominant period.

著者

Masayuki Hojo Junko Terada-Hirashima Haruhito Sugiyama

出版者

National Center for Global Health and Medicine

雑誌

Global Health & Medicine (ISSN:24349186)

巻号頁・発行日

pp.2020.01117, (Released:2021-03-09)

参考文献数

40

被引用文献数

8

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Angiotensin converting enzyme 2 (ACE2) and transmembrane protease serine 2 (TMPRSS2), two receptors on the cell membrane of bronchial epithelial cells, are indispensable for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. ACE2 receptor is increased among aged, males, and smokers. As smoking upsurges ACE2 expression, chronic obstructive pulmonary disease (COPD) patients are prone to SARS-CoV-2 infection, and are at a higher risk for severe forms of COVID-19 (coronavirus disease 2019) once infected. The expression of ACE2 and TMPRSS2 in asthma patients is identical (or less common) to that of healthy participants. ACE2 especially, tends to be low in patients with strong atopic factors and in those with poor asthma control. Therefore, it could be speculated that asthma patients are not susceptible to COVID-19. Epidemiologically, asthma patients are less likely to suffer from COVID-19, and the number of hospitalized patients due to exacerbation of asthma in Japan is also clearly reduced during the COVID-19 pandemic; therefore, they are not aggravating factors for COVID-19. Related academic societies in Japan and abroad still lack clear evidence regarding asthma treatment during the COVID-19 pandemic, and recommend that regular treatment including biologics for severe patients be continued.