Table 1.
Demographic and clinical characteristics of the children and the etiology of virus infections detected by PCR.
| Children visiting for RTI | Children visiting at the age of 2 or 13 months (n = 110) |
||
|---|---|---|---|
| (n = 120) | RTI symptoms (n = 33) | No symptoms (n = 77) | |
| Age (years) | 1.08 ± 0.42 | 0.64 ± 0.46 | 0.55 ± 0.44 |
| Sex | |||
| Male | 70 (58%) | 22 (67%) | 42 (55%) |
| Symptoms | |||
| Respiratory symptoms | 115 (96%) | 33 (100%) | 0 |
| Fever | 107 (89%) | 0 | 0 |
| Diagnoses | |||
| Acute upper RTI | 94 (78%) | NA | NA |
| Acute otitis media | 26 (22%) | NA | NA |
| Wheezing illness | 17 (14%) | NA | NA |
| Laryngitis | 4 (3%) | NA | NA |
| Laboratory values | |||
| Blood MxA (μg/l) | 855 (383–1438) | 220 (75–660) | 110 (60–185) |
| White blood cell count (E9/l) | 9.37 ± 4.07 | ND | ND |
| C-reactive protein (mg/l) | 13.6 ± 19.8 | ND | ND |
| Virus detection | |||
| Virus-positive | 100 (83%) | 24 (72%) | 12 (16%)a |
| Rhinovirus | 31 (26%) | 15 (45%) | 4 (5%) |
| Respiratory syncytial virus | 15 (13%) | 1 (3%) | 2 (3%) |
| Coronavirus OC43/HKU1 | 8 (7%) | 1 (3%) | 2 (3%) |
| Parainfluenza virus type 3 | 7 (6%) | 0 | 1 (1%) |
| Human metapneumovirus | 6 (5%) | 0 | 0 |
| Coronavirus 229E/NL63 | 1 (1%) | 3 (9%) | 2 (3%) |
| Human bocavirus | 4 (3%) | 1 (3%) | 0 |
| Influenza A virus | 3 (3%) | 1 (3%) | 0 |
| Parainfluenzavirus type 1 | 2 (2%) | 0 | 0 |
| Influenza B virus | 1 (1%) | 0 | 0 |
| Adenovirus | 1 (1%) | 0 | 0 |
| Parainfluenzavirus type 2 | 0 | 0 | 1 (1%) |
| Co-infection | 21 (18%)b | 2 (6%)c | 0 |
RTI, respiratory tract infection; NA, not available; ND, not determined.
Diagnoses, white blood cell counts and C-reactive protein levels were available for children visiting for RTI and examined by a physician. Part of the children (n = 33) visiting at the age of 2 or 13 months had mild symptoms of RTI at the time of sample collection, not necessitating an evaluation by a physician.
Values are n (%), mean ± SD, and for MxA, median (IQR).
The overall rate of virus detection in all screened asymptomatic children (n = 163) was 7%.
Co-infections (no.): Respiratory syncytial virus with either rhinovirus (2), parainfluenza virus (3), bocavirus (3), human metapneumovirus (1), coronavirus (1), adenovirus (1), or coronavirus and bocavirus (1); rhinovirus with coronavirus (3), bocavirus (1), parainfluenza virus (1), enterovirus (1), metapneumovirus (1), or parainfluenzavirus and bocavirus (1); coronavirus with bocavirus (1).
Co-infections: Bocavirus with either respiratory syncytial virus (1), or rhinovirus (1).