When we talk about the Corona pandemic today, which has been with us for a year now, there is good news and bad news. The good news is that if everyone works together and consistently implements the known measures, contagions and Covid-19 infection risks can be minimized. The bad news is that the crisis is far from over. The hope that the approved vaccines will relieve us of all worries in the short term is shattered for various reasons: On the one hand, several new viral mutations are appearing and, on the other hand, both vaccine refusers and vaccine supply shortages will continue to stand in the way of mass immunization for quite some time. According to recent experience, preventive testing is the safest prophylaxis among the known protection concepts.