title: Human bocavirus in patients with respiratory tract infection.
abstract: BACKGROUND
  Human bocavirus (HBoV) is a newly identified viral pathogen, and its clinical epidemiology and significance in respiratory infections have not yet been completely elucidated. We investigated the prevalence of HBoV infection and the association between viral (HBoV) load and clinical features of the infection in patients of all age-groups.
  
  
  METHODS
  Nasopharyngeal aspirates from patients with symptoms of respiratory infection were tested for presence of HBoV by using real-time polymerase chain reaction. HBoV-positive patients were categorized into low- and high-viral-load groups using 1.0×10(6) copies/mL as the threshold value of viral load.
  
  
  RESULTS
  Detection rate of HBoV was 4.8% (N=93) in a total of 1,926 samples with peak incidence of infection being observed in patients aged 6-12 months. HBoV infection was more frequently observed in young children, especially, in children aged less than 5 yr, and the HBoV load decreased with increase in age. HBoV was codetected with other respiratory viruses in 17 (18.3%) of the 93 HBoV-positive patients and 15 patients (88.2%) belonged to the low-viral-load group. Patients infected with HBoV alone showed a higher viral load than those patients in whom HBoV was codetected with other respiratory viruses (median load, 3.78×10(5) copies/mL vs. 1.94×10(4) copies/mL, P=0.014). Higher pulse rate (P=0.007) and respiratory rate (P=0.021) were observed in patients with a high-viral-load.
  
  
  CONCLUSIONS
  Our results suggest that HBoV may be the causative agent of respiratory infection in the high-viral-load group.
authors.affiliation: Department of Laboratory Medicine, Korea University College of Medicine, Seoul, Korea.
authors.forename: Jang Su
authors.initials: JS
authors.lastname: Kim
authors.forename: Chae Seung
authors.initials: CS
authors.lastname: Lim
authors.forename: Young Kee
authors.initials: YK
authors.lastname: Kim
authors.forename: Kap No
authors.initials: KN
authors.lastname: Lee
authors.forename: Chang Kyu
authors.initials: CK
authors.lastname: Lee
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D004279:DNA, Viral / Q000032:analysis; D005260:Female; D056661:Human bocavirus / Q000302:isolation & purification*; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D009305:Nasopharynx / Q000821:virology; D010322:Parvoviridae Infections / Q000175:diagnosis / Q000453:epidemiology* / Q000821:virology; D016133:Polymerase Chain Reaction; D015995:Prevalence; D012141:Respiratory Tract Infections / Q000175:diagnosis / Q000453:epidemiology* / Q000821:virology; D019562:Viral Load
chemical_list: D004279:DNA, Viral