Since its onset (Zhu et al., 2020), the coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), emerged to a major burden for the population in general but especially brought great challenges for the healthcare sector (Miller et al., 2020). Recent statistics presented by the German federal government agency Robert-Koch-Institute (RKI) show that cough, fever, nasal congestion, sore throat and loss of smell or taste are the most common symptoms caused by COVID-19 (RKI, 2021a).
