COVID 19: Pandemic assessment and management using Incidencecalc(t+14) and herd immunity - Habere nos alia modum?

The course of the COVID-19 pandemic is commonly evaluated using the 7-day Incidence. We propose using 1) Incidencecalc(t+14), an index for the theoretical course of the pandemic in the absence of lockdown, as a basis for making real-time interventions. 2) The derived parameters tα(t) and tα_stable(S), obtained with the SIZ algorithm and the Bateman function, for estimating of the required degree of herd immunity to stop the pandemic. The current value of tα(t) for Germany is ~ 1.8 days, indicating that the percentage herd immunity required to halt the pandemic, assuming an efficacy of vaccination of 90%, is at least 87%.