Infection with the novel coronavirus SARS-CoV-2 follows a highly variable course: some of those infected do not even notice it, while others become so seriously ill that their lives are placed at risk. Scientists from the Berlin Institute of Health (BIH) and Charité – Universitätsmedizin Berlin and their colleagues from Leipzig and Heidelberg have now discovered that the immune system has a decisive influence on the progression of the disease and sometimes causes greater damage than the virus itself. The researchers have now published their findings in the journal Nature Biotechnology.