Crude and adjusted values of mean and median age were lower in all COVID-19 case series compared with SPP (Table). The proportion of females differed between the case series, ranging from 32% in Wuhan to 59% in Zhejiang. The adjusted SPP showed a range from 39% to 42% in the proportions of females throughout the 5 years under consideration. The overall proportion of comorbidities was much smaller in the COVID-19 case series (range: 20–51%) than in German patients, where the proportion ranged from 70% to 77%, depending on the year. Hypertension and diabetes were the most important chronic comorbidities both among COVID-19 patients and among SPP. However, there were fewer patients with chronic obstructive pulmonary disease (COPD) or renal disease among COVID-19 patients than among SPP.