title: [Relation between clinical detection rates of the novel influenza virus A/H1N1 RNA in confirmed patients in Guangzhou and the disease course].
abstract: OBJECTIVE
  To study the relation of the detection rates of the novel influenza virus A/H1N1 RNA in clinically confirmed patients in the 2009 pandemic with the age distribution of the patients and the disease course.
  
  
  METHODS
  A total of 151 clinical patients with H1N1 infection were enrolled in this study, from whom 833 dynamic throat swab samples were obtained for detecting the H1N1 RNA using real-time PCR. A statistical analysis of the age distribution was performed among the patients with different disease courses. Chi-square for trend test was used to study the correlation between the detection rates of H1N1 RNA and the time of disease onset.
  
  
  RESULTS
  The majority of patients were young with their ages ranging from 10 to 20 years (57.26%) and 20 to 30 years (22.18%). Chi-square for trend test revealed that the positivity rates of the throat swabs in the patients decreased with the prolongation of the disease course (chi(2)=9.784, P=0.002).
  
  
  CONCLUSIONS
  Most of the H1N1 patients are young within the age range of 10-30 years, and the longest disease course can exceed 10 days. The positivity rates of throat swabs from the H1N1 patients decreases with the prolongation of the disease course.
authors.affiliation: Guangzhou Center for Disease Control and Prevention, Guangzhou 510080, China. junewhite@163.com
authors.forename: Zhi-Jun
authors.initials: ZJ
authors.lastname: Bai
authors.forename: Xin-Wei
authors.initials: XW
authors.lastname: Wu
authors.forename: Ye-Jian
authors.initials: YJ
authors.lastname: Wu
authors.forename: Mei-Xia
authors.initials: MX
authors.lastname: Li
authors.forename: Yang
authors.initials: Y
authors.lastname: Xu
authors.forename: Hua-Ping
authors.initials: HP
authors.lastname: Xie
authors.forename: Yi-Yun
authors.initials: YY
authors.lastname: Chen
authors.forename: Li-Yun
authors.initials: LY
authors.lastname: Jian
authors.forename: Yu-Fei
authors.initials: YF
authors.lastname: Liu
authors.forename: Tie-Gang
authors.initials: TG
authors.lastname: Li
authors.forename: Zhi-Cong
authors.initials: ZC
authors.lastname: Yang
authors.forename: Ming
authors.initials: M
authors.lastname: Wang
authors.forename: Biao
authors.initials: B
authors.lastname: DI
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D002648:Child; D002681:China / Q000453:epidemiology; D005260:Female; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype / Q000235:genetics*; D007251:Influenza, Human / Q000453:epidemiology / Q000821:virology*; D008297:Male; D010614:Pharynx / Q000821:virology; D012367:RNA, Viral / Q000032:analysis*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D055815:Young Adult
chemical_list: D012367:RNA, Viral