Case fatality risk by age from COVID-19 in a high testing setting in Latin America: Chile, March-May, 2020

Undurraga, Eduardo A; Chowell, Gerardo; Mizumoto, Kenji

Background Early severity estimates of COVID-19 are critically needed to better assess the potential impact of the ongoing pandemic in different socio-demographic groups. Using real-time epidemiological data from Chile, the nation in Latin America with the highest testing rate for COVID-19, we derive delay-adjusted severity estimates by age group as of May 18th, 2020. Methods We employed statistical methods and daily series of age-stratified COVID-19 cases and deaths reported in Chile to estimate the delay-adjusted case fatality rate across six age groups. Results Our most recent estimates of the time-delay adjusted case fatality rate are 0.08% (95% Credible Interval CrI:0.04-0.13%) among persons aged 0-39, 0.61% (95%CrI:0.41-0.87%) for those aged 40-49, 1.06% (95%CrI:0.76-1.40%) for those aged 50-59, 3.79% (95%CrI:3.04-4.66%) for those aged 60-69, 12.22% (95%CrI:10.40-14.38%) for those aged 70-79, and 26.27% (95%CrI:22.95-2980%) for persons aged 80 and over. The overall time-delay adjusted case fatality rate is1.78% (95%CrI: 1.63-1.95%) across all age groups. Conclusions Severity estimates from COVID-19 in Chile indicate a disproportionate impact among seniors, especially among those aged [≥] 70 years. COVID-19 is imposing a high death toll in Latin America. Case fatality rates in Chile suggest the health system is not yet overwhelmed, but the epidemic is expanding fast.