Estimating effective infection fatality rates during the course of the COVID-19 pandemic in Germany

Abstract Background The infection fatality rate (IFR) of the Coronavirus Disease 2019 (COVID-19) is one most discussed figures in context this pandemic. In contrast to case (CFR), IFR depends on total number infected individuals – not just confirmed cases. order estimate IFR, several seroprevalence studies have been or are currently conducted. Methods Using German COVID-19 surveillance data and age-group specific estimates from multiple international studies, work investigates time-dependent variations effective over course Three different methods for estimating (effective) IFRs presented: (a) population-averaged based assumption that risk independent age time, (b) distribution cases approximately reflects individuals, (c) accounting age- dark infections. Results Effective Germany estimated vary as distributions infections changing during particular first second waves spring autumn/winter 2020, there has a pronounced shift towards older groups, resulting larger estimates. temporary increase wave be smaller but still remains when adjusting figures. A comparison with observed CFRs indicates substantial fraction variability mortality can explained by changes Furthermore, vanishing gap between apparent after wave, while an increasing wave. Conclusions development CFR pandemic Germany. Further research warranted obtain timely age-stratified estimates, particularly light new variants virus.