title: [The virus isolation analysis of the H5N1 subtype human avain influenza cases in mainland China from 2005 to 2009].
abstract: OBJECTIVE
  To analyse the correlation between the virus isolation and the specimen collection of the H5N1 human high pathogenic avain influenza cases in Mainland China.
  
  
  METHODS
  The specimens were collected in Mainland China from 2005.10 to 2009.3 and the H5N1 viruses were isolated by passage in embryonated chicken eggs.
  
  
  RESULTS
  Most specimens were obtained within 14 days after disease onset. For the specimens collected within 7 days, the isolation rate was relatively high and the difference of the positive rate between different years was lower than those specimens collected after 7 days. Most of the samples in our study were collected from the upper or lower respiratory tract with few from blood, feces, et al. The isolation rate of lower respiratory specimens was higher and the difference of the positive rate between different years was relatively lower than those from upper respiratory specimens.
  
  
  CONCLUSIONS
  We suggest that the samples should be collected from lower respiratory tract during the acute phase to get the higher isolation rate.
authors: State Key Laboratory for Infectious Disease Prevention and Control, National Institute of Viral Disease Prevention and Control, China Center for Disease Prevention and Control, Beijing.
authors: Shu-mei
authors: SM
authors: Zou
authors: Ye
authors: Y
authors: Zhang
authors: Zi
authors: Z
authors: Li
authors: Jie
authors: J
authors: Dong
authors: Xin-sheng
authors: XS
authors: Zhao
authors: Li-bo
authors: LB
authors: Dong
authors: Le-ying
authors: LY
authors: Wen
authors: Cui-ling
authors: CL
authors: Xu
authors: Min
authors: M
authors: Wang
authors: Jun-feng
authors: JF
authors: Guo
authors: He-jiang
authors: HJ
authors: Wei
authors: Rong-bao
authors: RB
authors: Gao
authors: Xiu-ping
authors: XP
authors: Wang
authors: Yue-long
authors: YL
authors: Shu
mesh_terms: D000818:Animals; D002642:Chick Embryo; D002681:China / Q000453:epidemiology; D006801:Humans; D053124:Influenza A Virus, H5N1 Subtype / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D007251:Influenza, Human / Q000453:epidemiology / Q000821:virology*; D012137:Respiratory System / Q000821:virology