SARS-CoV-2 Omicron variants BA.1 and BA.2 both show similarly reduced disease severity of COVID-19 compared to Delta, Germany, 2021 to 2022
Sievers, Claudia and Zacher, Benedikt and Ullrich, Alexander and Huska, Matthew and Fuchs, Stephan and Buda, Silke and Haas, Walter and Diercke, Michaela and an der Heiden, Matthias and Kröger, Stefan, Eurosurveillance, 27, 2200396 (2022), https://doi.org/10.2807/1560-7917.ES.2022.27.22.2200396