Table 1 Comparison of clincial and laboratory characteristics of RSV and FLU patients; median and interquartile range are indicated for continuous variables; ns not significant

N (%)

476 (83.1%)

95 (16.6%)

Male

269/476 (56.5%)

55/95 (57.9%)

ns

Age, months

4 (2–8)

12 (5.5–18)

< 0.0001

Duration of illness, days

4 (2–5)

3 (2–5)

0.0005

Fever (≥38.0 °C)

330/476 (69.3%)

93/95 (97.9%)

< 0.0001

Body temperature on admission, °C

37.5 (37.1–38.3)

38.4 (37.5–39.3)

< 0.0001

Peak body temperature, °C

38.7 (37.7–39.4)

39.9 (39.1–40.1)

< 0.0001

Oxygen saturation at admission, %

97 (94–98)

98 (96–100)

0.0002

Minimal oxygen saturation, %

90 (88–94)

96 (90–98)

< 0.0001

Need for intensive care

16/476 (3.4%)

1/95 (1.1%)

ns

Length of stay, days

5 (4–7)

4 (3–6.5)

0.0023

Blood culture obtained

165/476 (34.7%)

54/95 (56.8%)

< 0.0001

CRP on admission, mg/L

6.9 (0–17.6)

6.6 (0–14.1)

ns

Peak CRP, mg/L

12.3 (5.8–29.2)

11.7 (5.4–23.7)

ns

WBC on admission, 10^9/L

10.7 (8.5–13.2)

10.8 (7.1–13.6)

ns

Chest radiography performed

135/476 (28.4%)

18/95 (18.9%)

ns

Infiltrate on chest radiogram

72/135 (53.3%)

13/18 (72.2%)

ns

Preexisting antibiotic therapy

32/476 (6.7%)

14/95 (14.7%)

0.0188

Well appearance

32/476 (6.7%)

6/95 (6.3%)

ns

Ill appearance

245/476 (51.5%)

62/95 (65.3%)

0.0176

Septic appearance

168/476 (35.3%)

23/95 (24.2%)

0.0426

Febrile seizure

3/476 (0.6%)

14/95 (14.7%)

< 0.0001

Acute otitis media

70/476 (14.7%)

33/95 (34.7%)

< 0.0001

Upper respiratory tract infection

0/476 (0%)

47/95 (49.5%)

< 0.0001

Bronchitis/Bronchiolitis

236/476 (49.6%)

6/95 (6.3%)

< 0.0001

Pneumonia

239/476 (50.2%)

21/95 (22.1%)

< 0.0001

Fever of unknown origin

1/476 (0.2%)

21/95 (22.1%)

< 0.0001

Death

0/476

1/95 (1.1%)

ns

Oxygen therapy

314/476 (66.0%)

23/95 (24.2%)

< 0.0001

Length of oxygen therapy, days

2 (0–5)

0

< 0.0001

Antibiotic therapy

136/476 (28.6%)

21/95 (22.1%)

0.2107