Abstract
Human bocavirus (HBoV) is a parvovirus recently identified in association with acute respiratory infections (ARI). Despite its worldwide occurrence, little is known on the pathogenesis of HBoV infections. In addition, few systematic studies of HBoV in ARI have been conducted in Latin America. Therefore, in order to test whether active viral replication of human bocavirus is associated with respiratory diseases and to understand the clinical impact of this virus in patients with these diseases, we performed a 3-year retrospective hospital-based study of HBoV in outpatients and inpatients with symptoms of Acute Respiratory Infections (ARI) in Brazil. Nasopharyngeal aspirates (NPAs) from 1015 patients with respiratory symptoms were tested for HBoV DNA by PCR. All samples positive for HBoV were tested by PCR for all other respiratory viruses, had HBoV viral loads determined by quantitative real time PCR and, when possible, were tested by RT-PCR for HBoV VP1 mRNA, as evidence of active viral replication. HBoV was detected in 4.8% of patients, with annual rates of 10.0%, 3.0% and 3.0% in 2005, 2006 and 2007, respectively. The range of respiratory symptoms was similar between HBoV-positive and HBoV-negative ARI patients. However, a higher rate of diarrhea was observed in HBoV-positive patients. High HBoV viral loads (>108 copies/mL) and diarrhea were significantly more frequent in patients with exclusive infection by HBoV and in patients with detection of HBoV VP1 mRNA than in patients with viral co-infection, detected in 72.9% of patients with HBoV. In summary, our data demonstrated that active HBoV replication was detected in a small percentage of patients with ARI and was correlated with concurrent diarrhea and lack of other viral co-infections.
Highlights
The discovery of human bocavirus (HBoV) was the result of a viral metagenomic study of respiratory secretions from Swedish children with symptoms of acute respiratory infection (ARI) reported in 2005 [1]
It was noticeable that HBoV circulated roughly along with human respiratory syncytial virus (HRSV) (Figure 1)
In this 3year study period, there was a trend for an increase in the total number of respiratory samples from children submitted for viral testing, HRSV and HBoV positivity, in association with dry season and declining average montly temperatures [22]
Summary
The discovery of human bocavirus (HBoV) was the result of a viral metagenomic study of respiratory secretions from Swedish children with symptoms of acute respiratory infection (ARI) reported in 2005 [1]. HBoV is often detected in patients with ARI [7,8,9], including those with wheezing, croup, cough, rhinorrhea and fever [2,10]. Symptoms associated with HBoV usually last 1–2 weeks [11,12], but the agent has been detected in association with prolonged fever [13]. An association of HBoV with respiratory disease has been based mostly on the significantly higher frequencies of detection of the agent in ARI patients than in control subjects without respiratory symptoms [8,10,14]. HBoV DNA has been detected in tonsil tissue in children with chronic tonsillitis undergoing surgical resection [17,18]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
