Defining high-value information for COVID-19 decision-making

Joshua A Salomon

We assume that the mortality risks among symptomatic individuals are 0%, 0.4%, and 5.4% for the 0-19, 20-64, and 65+ age groups, respectively. These values were derived from the age-stratified infection fatality ratios (IFR) calculated by Ferguson et al. (2020) (who in turn derived their estimates from work by Verity et al. (2020) , while also adjusting for a varying attack rate across age groups). Ferguson et al. (2020) provides an IFR for 10-year age bins (i.e., 0-9 years, 10-19 years, etc.). In order estimate the mortality risk for the three age groups used in this analysis, we calculated a weighted average of the IFR across the It is important to note, however, that the mortality risk values we assume here are somewhat different from other estimates of the mortality risk. Riou et al. (2020) , which adjusts crude fatality rates from Hubei province, China, to account for delayed mortality and unidentified cases, estimate that the case fatality risk is less than 0.05% among individuals 19 years of age and younger, between 0.19% and 2.7% for individuals between 20-59 years old, and is at least 9.5% for individuals older than 60. Because estimating the number of deaths is not a primary aim of this model, however, uncertainty in the mortality risk is unlikely to have a significant impact on the model results. The main effect of the uncertainty would be to slightly change the size of the recovered population, which would impact the rate of exposure for susceptible individuals, but likely not enough to affect the main conclusions of the analysis.