WIC COLLOQUIUM online Christian Dudel, Max Planck Institute for Demographic Research An indirect estimation method for the total number of COVID-19 infections May 13th 2020, 14:00 Abstract The number of COVID-19 infections is important for assessing the progression of the pandemic, as the number of confirmed cases may underestimate the total number. We develop an indirect method to estimate the total number of infections based on age-specific death counts and age-specific infection fatality rates (IFRs). We use remaining life expectancy to scale IFRs between countries to account for differences in age structure, health status, and health care system. Using data for 10 countries up to April 17, we estimate that on average the total number of infections is four times higher than the number of confirmed cases. Cross-country variation is high. For Italy, the estimated number of infected is six times the confirmed cases; for the U.S. twice the confirmed cases; and for Germany, where testing has been comparatively extensive, 1.2 times the confirmed cases. Comparing our results with findings from local seroprevalence studies suggest that the seroprevalence studies are not representative. Due to the COVID-19 pandemic, the seminar will be held online via Zoom. Please register online to participate: https://www.oeaw.ac.at/VID/Events/Calendar/WIC-Colloquium/registration/. Login information will be sent to registered participants on Tuesday, May 12th. For more information please see the attached file.