Main demographical and clinical features of infants with bronchiolitis
| SARS-CoV-2-positive bronchiolitis (n=16) | SARS-CoV-2-negative bronchiolitis (n=298) | P value | |
| Age in months, median (IQR) | 4 (3–4) | 5 (2–8) | 0.18 |
| Male sex, n (%) | 11 (68.7) | 193 (64.8) | 0.75 |
| Weight in kg, median (IQR) | 6.2 (5–7.3) | 6.5 (4.7–8.2) | 0.40 |
| History of prematurity, n (%) | 2 (12.5) | 47 (15.8) | 1.0* |
| Presence of at least one comorbidity, n (%) | 1 (6.3) | 45 (15.1) | 0.48* |
| Chronic pulmonary disease | 1 (6.2) | 18 (6.0) | 1.0* |
| Congenital heart disease | 0 (0.0) | 17 (5.7) | 1.0* |
| Genetic syndrome | 0 (0.0) | 11 (3.7) | 1.0* |
| Other | 0 (0.0) | 22 (7.4) | 0.61* |
| Positivity for at least one other virus, n (%) | 1 (6.3) | 40 (13.4) | 0.62* |
| Rhinovirus | 1 (6.3) | 27 (9.0) | |
| Adenovirus | 0 | 6 (2.0) | |
| Parainfluenza virus | 0 | 4 (1.3) | |
| Coronavirus NL63 | 0 | 3 (1.0) | |
| Metapneumovirus | 0 | 2 (0.7) | |
| Respiratory syncytial virus | 0 | 1 (0.3) | |
| Bocavirus | 0 | 1 (0.3) | |
| Enterovirus | 0 | 3 (1.0) | |
| SARS-CoV-2-positive parents, n (%) | |||
| Both parents | 7 (43.8) | 3 (1.0) | <0.0001* |
| Father | 0 (0.0) | 1 (0.3) | |
| Mother | 3 (18.7) | 5 (1.7) | |
*Fisher’s exact test.