| Sex, n (%) | | | | 0.2 |
| Male | 36 (36.7) | 12 (46.2) | 24 (33.3) | |
| Female | 62 (63.3) | 14 (53.8) | 48 (66.7) | |
| Age, years | 61 (51.0, 67.0) | 67 (54.2, 72.8) | 60 (49.0, 66.0) | 0.062 |
| Age group, n (%) | | | | 0.5 |
| 30–39 years | 6 (6.1) | 1 (3.8) | 5 (6.9) | |
| 40–49 years | 18 (18.4) | 4 (15.4) | 14 (19.4) | |
| 50–59 years | 23 (23.5) | 6 (23.1) | 17 (23.6) | |
| 60–69 years | 33 (33.7) | 7 (26.9) | 26 (36.1) | |
| ≥70 years | 18 (18.4) | 8 (30.8) | 10 (13.9) | |
| BMI, n (%) | | | | 0.2 |
| <25 kg/m2 | 33 (33.7) | 5 (19.2) | 28 (38.9) |
| ≥25 kg/m2 | 55 (56.1) | 18 (69.2) | 37 (51.4) | |
| Unknown | 10 (10.2) | 3 (11.5) | 7 (9.7) | |
| Number of comorbid conditions, n (%) | | | | 0.7 |
| 0 | 21 (21.4) | 7 (26.9) | 14 (19.4) | |
| 1 | 32 (32.7) | 8 (30.8) | 24 (33.3) | |
| ≥2 | 45 (45.9) | 11 (42.3) | 34 (47.2) | |
| Comorbidities, n (%) | | | | |
| Diabetes | 20 (20.4) | 4 (15.4) | 16 (22.2) | 0.5 |
| Hypertension | 42 (42.9) | 11 (42.3) | 31 (43.1) | >0.9 |
| Cardiovascular diseases | 16(16.3) | 4 (15.4) | 12 (16.7) | >0.9 |
| COPD | 1 (1.0) | 0 (0.0) | 1 (1.4) | >0.9 |
| Asthma | 1 (1.0) | 0 (0.0) | 1 (1.4) | >0.9 |
| Kidney disease | 2 (2.0) | 0 (0.0) | 2 (2.8) | >0.9 |
| Neurological diseases | 4 (4.1) | 2 (7.7) | 2 (2.8) | 0.3 |
| Cerebrovascular diseases | 2 (2.0) | 2 (7.7) | 0 (0.0) | 0.068 |
| Liver diseases | 4 (4.1) | 2 (7.7) | 2 (2.8) | 0.3 |
| Malignant tumour | 4 (4.1) | 2 (7.7) | 2 (2.8) | 0.7 |
| Overweight (BMI≥23 kg/m2) | 55 (56.0) | 13 (50.0) | 42 (58.0) | >0.9 |
| Systemic diseases | 2 (2.0) | 0 (0.0) | 2 (2.8) | 0.15 |
| Symptoms at onset of COVID-19, n (%) | | | | |
| Cough | 11 (11.2) | | | |
| Dyspnoea | 30 (30.6) | | | |
| Myalgia | 7 (7.1) | | | |
| Diarrhoea | 5 (5.1) | | | |
| Fatigue | 40 (40.8) | | | |
| Incubation period, days | 5 (3.0, 8.0) | 5 (3.0, 8.0) | 5.5 (3.0, 8.0) | 0.3 |
| Length of hospital stay, days | 16 (11.0, 24.0) | 15 (8.5, 26.8) | 17 (12.0, 23.5) | 0.7 |
| Vaccination, n (%) | | | | 0.13 |
| 1 dose, <2 weeks before infection | 19 (19.4) | 4 (15.4) | 15 (20.8) | |
| 1 dose, >2 weeks before infection | 5 (5.1) | 3 (11.5) | 2 (2.8) | |
| Not vaccinated | 74 (75.5) | 19 (73.1) | 55 (73.4) | |
| Highest respiratory support technique during hospitalisation, n (%) | | | | 0.049 |
| No supplemental oxygen required | 4 (4.1) | 1 (3.8) | 3 (4.2) | |
| Oxygen via nasal cannula or face mask | 76 (77.6) | 24 (92.3) | 52 (72.2) | |
| HFNC or NIV or IMV | 18 (18.4) | 1 (3.8) | 17 (23.6) | |
| Overall health, n (%) | | | | <0.001 |
| Same as before | 30 (31) | 18 (69) | 12 (17.0) | |
| Worse than before | 62 (63) | 5 (19) | 57 (79.0) | |
| Better than before | 6 (6.1) | 3 (12) | 3 (4.2) | |