COVIX—An Index Allowing for the Assessment of the Pandemic Situation Based on Infections and Hospitalisation Data

Monitoring and assessing the severity of the pandemic situation is one of the key challenges that public officials faced during the COVID-19 pandemic. Daily new infections may lead to flawed assessments, as infected individuals lead to different constraints imposed on the health care system amid varying pandemic determinants. On the other hand, hospitalisations or hospital bed occupancy may lead to outdated assessments, as the corresponding data are only observable with considerable delay. In this study, we introduce a hospital beds model, which relates the three quantities of daily new infections, daily hospitalisation rates, and daily hospital bed occupancy in the context of the COVID-19 pandemic. Using this model, we develop COVIX—a severity index that assesses the impact of a pandemic in comparison to a specified reference date while taking infection and disease risks into account. The developed methodology and its implications are illustrated on data for the German federal state of Bavaria.