Fig. 1
From: Time-dependent risk of COVID-19 death with overwhelmed health-care capacity in Japan, 2020–2022
Epidemic curves of COVID-19 in Tokyo (A) and Osaka (B), 2020–2022. Grey bars represent reported number of confirmed cases, and dots indicate observed number of daily deaths as a function of the date of death. Vertical dashed lines separate the discrete time periods by pandemic wave, which we used to estimate the time-dependent case fatality risk as a step function. The lines indicate 1 June 2020, 1 December 2020, 1 March 2021, 1 July 2021, and 1 January 2022. Where there was a dominant variant of concern responsible for the epidemic wave, the arrows show the corresponding period. Vertical arrows indicate when vaccination started