title: Human bocavirus and acute wheezing in children.
abstract: BACKGROUND
  Human bocavirus is a newly discovered parvovirus. It has been detected primarily in children with acute lower respiratory tract infection, but its occurrence, clinical profile, and role as a causative agent of respiratory tract disease are not clear.
  
  
  METHODS
  We investigated the presence of human bocavirus by quantitative polymerase chain reaction of nasopharyngeal aspirate specimens and selected serum samples obtained from 259 children (median age, 1.6 years) who had been hospitalized for acute expiratory wheezing. The samples were analyzed for 16 respiratory viruses by polymerase chain reaction, virus culture, antigen detection, and serological assays.
  
  
  RESULTS
  At least 1 potential etiologic agent was detected in 95% of children, and >1 agent was detected in 34% of children. Human bocavirus was detected in 49 children (19%). A large proportion of the cases were mixed infections with other viruses, but human bocavirus was the only virus detected in 12 children (5%). High viral loads of human bocavirus were noted mainly in the absence of other viral agents, suggesting a causative role for acute wheezing. In addition, infections that had uncertain clinical relevance and low viral loads were prevalent. Human bocavirus DNA was frequently detected in serum specimens obtained from patients with acute wheezing, suggesting systemic infection.
  
  
  CONCLUSIONS
  Human bocavirus is prevalent among children with acute wheezing and can cause systemic infection. Results suggest a model for bocavirus infection in which high viral loads are potentially associated with respiratory symptoms and low viral loads indicate asymptomatic shedding. Therefore, quantitative polymerase chain reaction analysis may be important for additional studies of human bocavirus.
authors.affiliation: Department of Microbiology Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden. tobias.allander@karolinska.se
authors.forename: Tobias
authors.initials: T
authors.lastname: Allander
authors.forename: Tuomas
authors.initials: T
authors.lastname: Jartti
authors.forename: Shawon
authors.initials: S
authors.lastname: Gupta
authors.forename: Hubert G M
authors.initials: HG
authors.lastname: Niesters
authors.forename: Pasi
authors.initials: P
authors.lastname: Lehtinen
authors.forename: Riikka
authors.initials: R
authors.lastname: Osterback
authors.forename: Tytti
authors.initials: T
authors.lastname: Vuorinen
authors.forename: Matti
authors.initials: M
authors.lastname: Waris
authors.forename: Annelie
authors.initials: A
authors.lastname: Bjerkner
authors.forename: Annika
authors.initials: A
authors.lastname: Tiveljung-Lindell
authors.forename: Bernadette G
authors.initials: BG
authors.lastname: van den Hoogen
authors.forename: Timo
authors.initials: T
authors.lastname: Hyypiä
authors.forename: Olli
authors.initials: O
authors.lastname: Ruuskanen
mesh_terms: D000208:Acute Disease; D000305:Adrenal Cortex Hormones / Q000627:therapeutic use; D001483:Base Sequence; D052660:Bocavirus / Q000302:isolation & purification*; D002648:Child; D002675:Child, Preschool; D004279:DNA, Viral / Q000032:analysis; D005260:Female; D005387:Finland; D005500:Follow-Up Studies; D006760:Hospitalization; D006801:Humans; D007223:Infant; D008297:Male; D008969:Molecular Sequence Data; D010322:Parvoviridae Infections / Q000175:diagnosis* / Q000453:epidemiology; D015995:Prevalence; D012135:Respiratory Sounds; D012141:Respiratory Tract Infections / Q000175:diagnosis / Q000188:drug therapy / Q000821:virology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D018570:Risk Assessment; D012720:Severity of Illness Index
chemical_list: D000305:Adrenal Cortex Hormones; D004279:DNA, Viral