In one study, the symptoms of 81 "middle-aged" adults, who were between 50 and 64 years old, were recorded as follows:

• Fever: 63 patients (77.8%)
• Cough: 37 patients (45.7%)
• Dyspnea: 5 patients (6.2%)
• Fatigue: 26 patients (32.1%)
• Headache: 7 patients (8.6%)
• Respiratory rate: 19.9 $\pm$ 3.5
• Oxygen saturation: 93.3 $\pm$ 2.7

Maximum body temperature was:

• Below 37 degrees Celsius: 18 patients (22.2%)
• 37 or 38 degrees Celsius: 34 patients (42.0%)
• Above 38 degrees Celsius: 29 patients (35.8%)