In the respective observational time period of our cases, the mortality of mechanically ventilated COVID-19 patients in ICUs in Germany remained at 50% across age groups even with introduction of additional therapeutic measures like early corticosteroids/dexamethasone or IL-6 blockade (Karagiannidis et al. 2021; Kluge et al. 2021; Wilkinson 2020). Here, IL6 is linked to COVID-19.