title: [Spatiotemporal characteristics of seasonal influenza in mainland China].
abstract: OBJECTIVE
  To study the spatiotemporal distribution and seasonal characteristics of influenza and to explore its transmission patterns, in the mainland of China.
  
  
  METHODS
  Spatiotemporal cluster methods and spatial trend surface methods were used to analyze the influenza surveillance data.
  
  
  RESULTS
  There were a summer peak in the south from June to August (RR(paediatric) = 1.31, P < 0.01; RR(internal) = 1.74, P < 0.01) and a winter peak from December to January (RR(paediatric) = 1.45, P < 0.01; RR(internal) = 1.45, P < 0.01) in the northern part of the country, during every epidemic season. Influenza virus in mainland China seemed to spread from the southern to the northern parts of the country, in a progressing way.
  
  
  CONCLUSIONS
  In the southern part of the country, it is more important to take prevention and control measurements on influenza from June to August but for the northern part, the key period is from December to January. It is more important to timely identify the variation of the influenza virus, in the southern part of the country.
authors.affiliation: State Key Laboratory for Molecular Virology and Genetic Engineering, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 100052, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Gao
authors.forename: Li-qun
authors.initials: LQ
authors.lastname: Fang
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhang
authors.forename: Quan
authors.initials: Q
authors.lastname: Qian
authors.forename: Ya-pin
authors.initials: YP
authors.lastname: Li
authors.forename: Cui-ling
authors.initials: CL
authors.lastname: Xu
authors.forename: Ye
authors.initials: Y
authors.lastname: Zhang
authors.forename: Lei
authors.initials: L
authors.lastname: Yan
authors.forename: Hua
authors.initials: H
authors.lastname: Yang
authors.forename: Yan-chen
authors.initials: YC
authors.lastname: Bai
authors.forename: Hong
authors.initials: H
authors.lastname: Yang
authors.forename: Wu-chun
authors.initials: WC
authors.lastname: Cao
authors.forename: Yue-long
authors.initials: YL
authors.lastname: Shu
mesh_terms: D002648:Child; D002681:China / Q000453:epidemiology; D005843:Geography; D006801:Humans; D007251:Influenza, Human / Q000453:epidemiology* / Q000821:virology; D009975:Orthomyxoviridae; D012189:Retrospective Studies; D012621:Seasons