Table 3.

Comparison of Patient Characteristics and Disease Severity in Patients With RSV Mono‐Infections, Multiple Infections Including RSV and Infections Caused by Viral Pathogens Excluding RSV

	RSV mono (N = 61)	RSV multiple (N = 43)	RSV negative (N = 38)	P‐values
Age (mo), median (IQR)	2.0 ± 0.39	5.6 ± 0.84	5.4 ± 0.80	P < 0.0013
Age < 3 mo	46 (75%)	15 (35%)	15 (39%)	P < 0.0013
Male	41 (67%)	25 (58%)	21 (55%)
Birth characteristics
Birth weight (grams), mean ± SD	3251 ± 778	3281 ± 700	3255 ± 817
Prematurity1	9 (15%)	6 (14%)	3 (8%)
Maternal smoking	12/59 (20%)	6/40 (15%)	4/31 (13%)
Breastfeeding	33/60 (53%)	29/41 (71%)	20/37 (54%)
Underlying diseases2
CHD	1 (2%)	2 (5%)	5 (13%)	P = 0.034
Environmental factors
Atopic disease	6 (10%)	6/42 (14%)	6/37 (16%)
Atopic family history	34/59 (58%)	19/42 (45%)	23/35 (66%)
Passive smoking	9/59 (15%)	4/42 (10%)	6/33 (18%)
Siblings	50 (82%)	33 (77%)	27/37 (73%)
Daycare attendance	1 (2%)	13/41 (32%)	11/36 (31%)	P < 0.0013
Viral load
RSV Ct value, mean ± SD	27.2 ± 5.1	28.3 ± 4.4
Mild	26.5 ± 7.2	29.2 ± 4.9
Moderate	27.2 ± 4.8	28.1 ± 3.7
Severe	27.5 ± 4.3	26.0 ± 3.4
Disease severity				P = 0.0025
Mild	11 (18%)	18 (42%)	12 (32%)
Moderate	28 (46%)	19 (44%)	17 (45%)
Severe	22 (36%)	6 (14%)	9 (24%)

Data are presented as number (%), unless otherwise specified.

IQR, interquartile range; SD, standard deviation; CHD, congenital heart defect; mo, months.

¹Prematurity was defined as a gestation age of 35 weeks or less.

²No patients with chronic lung diseases or immune deficiencies were included. Kruskall–Wallis non‐parametric or X² tests were performed, and were, if significant, followed by Mann–Whitney U‐tests or Chi‐squared tests for individual comparisons.

³RSV negative versus RSV mono and RSV negative versus RSV multiple.

⁴RSV negative versus RSVmono.

⁵RSV multiple versus RSV mono.