question: COVID-19 is the infectious disease caused by coronavirus SARS-CoV-2. The most common symptoms of COVID-19 are dry cough, tiredness and fever. Most patients recover from COVID-19 within a few weeks, but some patients have symptoms lasting for weeks or even months after recovery from acute illness, such as fatigue, shortness of breath and cough. This is a review of what we currently know about the clinical disease and its severity as well as which diagnostic strategies are recommended during and after hospital admission.