title: [Antigenic and genetic study of influenza virus B circulated in China in 2004-2005].
abstract: BACKGROUND
  To analyze the genetic and antigenic characteristics of hemagglutinin (HA) gene of human influenza B virus isolated from the mainland of China since 2004-2005.
  
  
  METHODS
  The single-way hemagglutinin inhibition (HI) tests were used to test the antigenic characteristics, and the HA1 gene was sequenced based on the antigenic results.
  
  
  RESULTS
  The Yamagata-like and Victoria-like viruses co-circulated in 2004-2005. For the Yamagata-like virus, the single-way HI results showed that 3.7% and 4.5% of the viruses had 4-fold greater HI titer difference compared with B/Shanghai/361/02 in 2004 and 2005, respectively. The HA1 sequence data showed that the virus had amino acid mutation, and there was one more glycosylation site at 196th site. For the Victoria-like virus, the single-way HI results showed that 8.5% and 20.6% of the viruses had 4-fold greater HI titer difference compared with B/Hong kong/330/01 in 2004 and 2005, respectively. The HA1 sequence data showed that the virus had replacement of 9 amino acids, and there was one more glycosylation site at 197th site.
  
  
  CONCLUSIONS
  The results showed that influenza B viruses had changed antigenic and genetic characteristics compared with B/Shanghai/361/02, B/Hong kong/330/01 in 2004-2005.
authors.affiliation: Chinese Influenza Center, Institute for Viral Disease Control and Prevention, State Key Laboratory for Infectious Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 100052, China.
authors.forename: Ye
authors.initials: Y
authors.lastname: Zhang
authors.forename: Le-ying
authors.initials: LY
authors.lastname: Wen
authors.forename: Xiang
authors.initials: X
authors.lastname: Zhao
authors.forename: Zi
authors.initials: Z
authors.lastname: Li
authors.forename: Jun-feng
authors.initials: JF
authors.lastname: Guo
authors.forename: Cui-ling
authors.initials: CL
authors.lastname: Xu
authors.forename: Min
authors.initials: M
authors.lastname: Wang
authors.forename: Hong-jie
authors.initials: HJ
authors.lastname: Yu
authors.forename: Wei-zhong
authors.initials: WZ
authors.lastname: Yang
authors.forename: Yuan-ji
authors.initials: YJ
authors.lastname: Guo
authors.forename: Yue-long
authors.initials: YL
authors.lastname: Shu
mesh_terms: D000956:Antigens, Viral / Q000097:blood; D002681:China / Q000453:epidemiology; D019267:Hemagglutinin Glycoproteins, Influenza Virus / Q000235:genetics; D006801:Humans; D009981:Influenza B virus / Q000145:classification / Q000235:genetics* / Q000276:immunology*; D007251:Influenza, Human / Q000453:epidemiology / Q000821:virology*; D010802:Phylogeny; D012367:RNA, Viral / Q000235:genetics / Q000302:isolation & purification; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA
chemical_list: D000956:Antigens, Viral; D019267:Hemagglutinin Glycoproteins, Influenza Virus; D012367:RNA, Viral