title: Distinctive clinical features of human bocavirus in children younger than 2 years.
abstract: OBJECTIVE
  Clinical characteristics of human bocavirus (HBoV) infection have been studied worldwide, but their importance of those characteristics remains unknown. We investigated distinctive clinical features of HBoV-positive children with lower respiratory tract infection (LRTI).
  
  
  RESULTS
  During April 2007-July 2009, for 402 hospitalized children younger than 2 years with LRTI, we prospectively examined virus genomes in nasopharyngeal swabs for HBoV, respiratory syncytial virus (RSV), rhinovirus, metapneumovirus, parainfluenzavirus, and adenovirus. The HBoV genomes were identified in 34 patients (8.5%). Clinical and laboratory data of HBoV-positive and other virus/bacteria-negative patients (n = 18) were analyzed and compared with data of RSV-single positive patients (n = 99). The seasonal distribution of HBoV exhibits a concentration of cases during March-September, with most RSV cases occurring during winter in Japan. The minimum age of HBoV-positive patients was 5 months, although 44 patients (44%) with RSV were younger than 6 months. The main clinical features were respiratory distress and hypoxia. Hypoxia advances within 3 days after onset. The mean oxygen saturation on arrival was 92.8%, which was significantly lower than that in patients with RSV (p < 0.001). White blood cell counts were similar among groups. However, the percentage of neutrophils in white blood cells were significantly higher in HBoV-positive patients (62 vs. 45%, p < 0.001). Their prognoses were good. Their hospital stays were 6.6 days.
  
  
  CONCLUSIONS
  HBoV-single positive patients show several clinical characteristics, such as seasonality, age, hypoxia, and neutrophilia, which differ from those with RSV infection.
authors.affiliation: Department of Pediatrics, Tokyo Women's Medical University Yachiyo Medical Center, 477-96 Owada-shinden, Yachiyo, Chiba 276-8524, Japan.
authors.forename: Yoko
authors.initials: Y
authors.lastname: Moriyama
authors.forename: Hiromichi
authors.initials: H
authors.lastname: Hamada
authors.forename: Mineyuki
authors.initials: M
authors.lastname: Okada
authors.forename: Nozomi
authors.initials: N
authors.lastname: Tsuchiya
authors.forename: Hiromi
authors.initials: H
authors.lastname: Maru
authors.forename: Yuri
authors.initials: Y
authors.lastname: Shirato
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Maeda
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Hirose
authors.forename: Masaki
authors.initials: M
authors.lastname: Yoshida
authors.forename: Yoh
authors.initials: Y
authors.lastname: Omura
authors.forename: Takafumi
authors.initials: T
authors.lastname: Honda
authors.forename: Ayako
authors.initials: A
authors.lastname: Muto
authors.forename: Kitami
authors.initials: K
authors.lastname: Hayashi
authors.forename: Masaru
authors.initials: M
authors.lastname: Terai
mesh_terms: D000367:Age Factors; D004417:Dyspnea / Q000821:virology; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data; D056661:Human bocavirus / Q000302:isolation & purification*; D006801:Humans; D000860:Hypoxia / Q000821:virology*; D007223:Infant; D007297:Inpatients; D007564:Japan / Q000453:epidemiology; D008297:Male; D009503:Neutropenia / Q000821:virology*; D010100:Oxygen / Q000378:metabolism; D010322:Parvoviridae Infections / Q000175:diagnosis* / Q000453:epidemiology / Q000821:virology; D011379:Prognosis; D011446:Prospective Studies; D018357:Respiratory Syncytial Virus Infections / Q000175:diagnosis* / Q000453:epidemiology; D012136:Respiratory Syncytial Viruses / Q000302:isolation & purification; D012141:Respiratory Tract Infections / Q000175:diagnosis* / Q000453:epidemiology / Q000821:virology*; D012621:Seasons; D013997:Time Factors
chemical_list: D010100:Oxygen
references.citation: N Engl J Med. 2003 May 15;348(20):1953-66
references.pmid: 12690092
references.citation: Proc Natl Acad Sci U S A. 2005 Sep 6;102(36):12891-6
references.pmid: 16118271
references.citation: Clin Infect Dis. 2007 Apr 1;44(7):904-10
references.pmid: 17342639
references.citation: J Clin Virol. 2008 May;42(1):72-4
references.pmid: 18296108
references.citation: Pediatr Infect Dis J. 2008 Nov;27(11):969-73
references.pmid: 18833027
references.citation: Emerg Infect Dis. 2006 May;12(5):862-3
references.pmid: 16710957
references.citation: J Clin Microbiol. 2000 Mar;38(3):1191-5
references.pmid: 10699020
references.citation: Clin Microbiol Rev. 2008 Apr;21(2):291-304, table of contents
references.pmid: 18400798
references.citation: Arch Dis Child. 2010 Jan;95(1):35-41
references.pmid: 19822538
references.citation: Nat Med. 2001 Jun;7(6):719-24
references.pmid: 11385510
references.citation: J Clin Microbiol. 2006 Mar;44(3):1132-4
references.pmid: 16517912
references.citation: Pediatr Infect Dis J. 2008 Aug;27(8):677-80
references.pmid: 18574440
references.citation: J Infect. 2008 Feb;56(2):137-42
references.pmid: 18164764
references.citation: Lancet. 2005 Mar 26-Apr 1;365(9465):1147-52
references.pmid: 15794969
references.citation: Pediatr Infect Dis J. 2009 Nov;28(11):1035-6
references.pmid: 19859020
references.citation: J Infect Dis. 2002 Jun 1;185(11):1660-3
references.pmid: 12023774
references.citation: N Engl J Med. 2003 May 15;348(20):1967-76
references.pmid: 12690091
references.citation: Aviat Space Environ Med. 2004 Sep;75(9):811-7
references.pmid: 15460635
references.citation: J Infect Dis. 2006 Nov 1;194(9):1283-90
references.pmid: 17041855
references.citation: J Clin Microbiol. 1993 Sep;31(9):2544-6
references.pmid: 7691879
references.citation: J Virol. 2009 Aug;83(15):7739-48
references.pmid: 19474096
references.citation: Arch Virol. 2007 Jan;152(1):1-9
references.pmid: 16957827
references.citation: J Clin Virol. 2008 Oct;43(2):142-7
references.pmid: 18644746
references.citation: Emerg Infect Dis. 2006 Sep;12(9):1457-8
references.pmid: 17073104
references.citation: J Clin Microbiol. 2007 Oct;45(10):3218-23
references.pmid: 17699639
references.citation: J Med Virol. 2003 Jan;69(1):132-44
references.pmid: 12436489
references.citation: Lancet. 2003 Apr 19;361(9366):1319-25
references.pmid: 12711465