New challenges have arisen due to the much more contagious Delta variant, which has been the predominant variant in Germany since the middle of the year. We investigate the effects of various measures discussed in politics and the media. We show that, in general, measures that explicitly include already immunized people -- for example, through regular testing -- work better. According to our simulations, the currently envisaged measures "2G+ in public (recreational) facilities" plus "3G/home office at work" plus "rapid boosting" in federal states with high vaccination rates could be sufficient to push the R-value below 1 and thus slow down the currently rapidly increasing number of cases (see sections 3 and 4).

In addition, we explain that infection control measures should consider all population groups, as the different groups all contribute, albeit differently, to the burden on the health care system (see sections 5 and 6).
