Background: Human Bocavirus (HBoV), a new species of the genus parvovirus newly detected in 2005, seems to be a worldwide distributed pathogen among children with respiratory tract infection (prevalence 2%-18%). Recently published retrospective studies and one prospective birth cohort study suggest that HBoV-primary infection occurs in infants.
Methods: Prospective single center study over one winter season (November 2005-May 2006) with hospitalized children without age restriction using PCR-based diagnostic methods.
Results: HBoV DNA was detected in 11 (2.8%) of 389 nasopharyngeal aspirates from symptomatic hospitalized children (median age 9.0 months; range: 3-17 months). RSV, HMPV, HCoV, and Influenza B were detected in 13.9% (n=54), 5.1% (n=20), 2.6% (n=10), and 1.8% (n=7), respectively. There was no influenza A DNA detected in any of the specimens. The clinical diagnoses were acute wheezing (bronchitis) in four patients, radiologically confirmed pneumonia in six patients (55%) and croup syndrome in one patient. In five to six patients with pneumonia, HBoV was the only pathogen detected. While no patient had to be mechanically ventilated, 73% needed oxygen supplementation. In four (36.4%) patients at least one other viral pathogen was found (plus RSV n=3; 27.3%; Norovirus n=1; 9.1%).
Conclusion: HBoV causes severe respiratory tract infections in infants and young children. Its role as a copathogen and many other open questions has to be defined in further prospective studies.