Fig. 1

Details of upper and lower respiratory symptoms. a Ratio of upper respiratory symptoms in Group 2. Of 331 patients in Group 2, 136 patients (41.1%) developed two or more upper respiratory symptoms at the same time. b Number of patients with each upper respiratory symptom in Group 2. Of 331 patients in Group 2, 149 patients developed sore throat, the most frequent upper respiratory symptom. Dysosmia and dysgeusia were also as common as sore throat. c Ratio of lower respiratory symptoms in Group 3. Of 1229 patients in Group 3, 549 patients (44.6%) developed a single lower respiratory symptom. d Number of patients with each lower respiratory symptom in Group 3. Of 1229 patients in Group 3, 988 patients presented with cough and 695 patients with dyspnea. The frequency of sputum production was the lowest