Human bocavirus and other respiratory viral infections in a 2‐year cohort of hospitalized children

Abstract

Human bocavirus (HBoV) infection is reported worldwide and may cause severe respiratory tract infections. The aim of the present study was to assess the prevalence of HBoV, and other respiratory viral pathogens, in a 2-year retrospective study of children admitted to hospital, and to investigate whether viral loads of HBoV DNA were associated with severity of infection. Between April 2007 and March 2009, 891 respiratory samples from 760 children admitted to hospital with acute respiratory tract infection were tested for the presence of respiratory viruses by real-time PCR or direct immunofluorescence testing. HBoV DNA was detected by using internally controlled real-time quantitative PCR assay and 25 samples selected at random were sequenced. The virus detected most frequently was rhinovirus, followed by respiratory syncytial virus, HBoV, and human metapneumovirus. HBoV DNA was detected in 18.4% of children admitted to hospital. HBoV was the only viral pathogen detected in 66/164 (40.2%) of HBoV DNA-positive children and in 7.4% of all 891 samples. Ninety-seven percent (64/66) of children with an HBoV single infection were diagnosed as having lower respiratory tract infection. Median HBoV DNA viral load was significantly higher in children when HBoV was detected as a single pathogen. Higher HBoV DNA viral loads were associated with prematurity and age. HBoV seems to be an important and frequent pathogen in respiratory tract infections in children, and it is likely that the severity of illness is comparable to the severity of RSV illness.

Determining Persistence of Bocavirus DNA in the Respiratory Tract of Children by Pyrosequencing

“…( 14 ) For HBoV1, increasing evidence supports its role as a respiratory pathogen associated with acute URI, LRI and AOM in young children. ( 4–6, 9, 22, 23, 27, 29 ) In this study, even with lack of serology to confirm acute infection, the absence of other co-infecting respiratory viruses during URI and previously HBoV1-negative samples suggest that new HBoV1 infection is highly associated with AOM following URI (8 out of 15 episodes). This finding supports a possible association with AOM development as described by others.…”

“…( 4 ) Nonetheless, increasing evidence confirms the association of HBoV1 with both upper and lower respiratory tract infections (URI and LRI), and acute otitis media (AOM) in young children. ( 2, 4–9 ) A recent study suggested that acquired immunity could be achieved by age 6, with a median of 2.3 years, ( 5 ) making an acute HBoV1 infection more likely during childhood. Prolonged HBoV1 presence in nasopharyngeal secretions has been described for up to 6 months ( 8,10 ) and identified in healthy asymptomatic children.…”

Human bocavirus in hospitalized children under 5 years with acute respiratory infection, São Paulo, Brazil, 2010

“…Our results suggested that neither viral load nor age range are directly associated to clinical manifestations and disease severity among HBoV infections in children <5 years of age. Nevertheless, a direct relationship between disease severity and HBoV load has been reported in previous studies [30][31][32]. Unfortunately, our study design and sample size did not allow us to draw conclusions to confirm or refute these findings.…”

Update on Human Rhinovirus and Coronavirus Infections

“…[125][126][127][128] Studies in children have reported a range of 0 to 52% positive specimens for HRV (►Table 2). [129][130][131][132][133][134][135][136][137][138][139][140][141][142][143][144][145][146][147][148] Bronchiolitis in children has been commonly reported in infants and young children. The most commonly reported virus recovered in acute cases has been RSV.…”