Human bocavirus frequency in pre-school and school-aged hospitalized wheezing children and association to epidemiological risk factors of wheezing

Recurrent wheezing in infancy is associated with acute respiratory infection (ARI) and atopy. The objectives of this work were to determine the frequency of respiratory human bocavirus (HBoV) in children hospitalized with acute wheezing and associated clinical-epidemiological variables. A cross-section observational study was performed. Nasal and pharyngeal swabs were obtained from pediatric patients hospitalized with acute wheezing and HBoV DNA was detected by PCR. Clinical and epidemiological data of patients were analyzed in relation with HBoV detection. Eight of 40 patients studied (20%) were pre-school age children (? 4 years old; average 3.5±0.5 yr.) and 32/40 (80%) were school-age children (5 to 14 years old; average 7.8±2.8 yr.). HBoV genome was detected in 22/40 patients (55%; IC95%: 40-69%), the majority of them school-aged children (19/22, 86.4%). No statistically significant differences were observed when comparing HBoV prevalence in groups of patients clustered by sex, age, antecedents of rhinitis, number of wheezing episodes in the previous year, and family history of atopy. Significant association was found between HBoV detection and (a) passive smoking: 17/23 (73.9%) patients with exposure to cigarette smoke were HBoV+ (p=0.006); (b) contact with cohabitant with ARI: 11/12 (91.7%) patients living with a cohabitant with ARI were HBoV+ (p=0.002). HBoV was frequent among school-age hospitalized wheezing children. HBoV genome detection was associated with passive smoking and contact with cohabitant with ARI.