Clinical characteristics of human bocavirus infections compared with other respiratory viruses in Spanish children

Background: Human bocavirus (HBoV) can be found in a substantial proportion of children with respiratory tract diseases. The relative importance of HBoV in viral respiratory tract illnesses is not yet well known. Objective: In this study, we looked for HBoV in pediatric patients to determine the incidence of HBoV as single infection and compared it with other commonly found respiratory viruses to describe the clinical differences associated with HBoV infections in children. Patients and Methods: A prospective study was conducted on children less than 14 years old, admitted with respiratory infection from September 2005 to August 2007 to the Pediatrics Department of the Severo Ochoa Hospital, Madrid, Spain. We studied the frequency of HBoV and 15 other respiratory viruses in nasopharyngeal aspirates and compared the clinical course of the infections caused by HBoV with those caused by other common respiratory viruses. Results: Positive results were confirmed in 435 (61.2%) of the 7 10 children studied. A single virus was detected in 308 patients. HBoV was found in 99 (13.9%) samples, but it was recovered as a single virus in only 35. Most of patients with HBoV infection (75%) were aged <= 26 months. The most common clinical diagnosis was recurrent wheezing (53%), followed by bronchiolitis (32%). Clinical differences were observed between HBoV and respiratory syncytial virus (RSV) infections (children were older and bronchiolitis less frequent), adenovirus (fever less frequent in HBoV group), and rhinovirus-associated infections (loss hypoxia in HBoV group). Conclusions: HBoV was the fourth most frequent single virus after RSV, rhinovirus, and adenovirus in children hospitalized because of respiratory infection. It was associated with recurrent wheezing and bronchiolitis showing a different clinical course from other virus in terms of diagnosis, fever, and age.