title: Influenza associated mortality in Southern China, 2010-2012.
abstract: OBJECTIVE
  Influenza caused substantial morbidity and mortality worldwide. The mortality burden caused by influenza has been under evaluation; however, data assessing this burden have been relatively sparse in tropical or subtropical regions. We estimated influenza-associated mortality in Guangzhou, China and assessed the excess mortality due to different influenza virus subtypes.
  
  
  METHODS
  We estimated influenza-associated excess mortality due to all-cause, pneumonia and influenza, cardiorespiratory disease and other influenza-associated diagnoses from weekly numbers of deaths and influenza surveillance data through negative binomial regression model during 2010-2012.
  
  
  RESULTS
  Estimates derived from the model indicated that influenza resulted in 14.72 (95% confidence interval (CI), 12.12-17.31) deaths per 100,000 population per year from all-cause death among all ages group. Most deaths (84.2%) occurred among people aged ≥65 years. B virus caused 5.84 (95%CI, 4.10-7.58) deaths per 100,000 population for all-cause death, which was higher than A (H3N2) (4.89, 95%CI, 3.19-6.59) or A(H1N1)pdm09 (3.99, 95%CI, 2.32-5.66).
  
  
  CONCLUSIONS
  Influenza is responsible for a substantial mortality especially among people aged ≥65 years and influenza B virus caused the highest influenza-associated mortality. The results highlight the need for seasonal influenza vaccination programs in subtropical areas to decrease excess mortality.
authors.affiliation: Guangzhou Center for Disease Control and Prevention, Guangzhou, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Wang
authors.affiliation: Guangzhou Center for Disease Control and Prevention, Guangzhou, China.
authors.forename: Chuanxi
authors.initials: C
authors.lastname: Fu
authors.affiliation: Guangzhou Center for Disease Control and Prevention, Guangzhou, China.
authors.forename: Kuibiao
authors.initials: K
authors.lastname: Li
authors.affiliation: Guangzhou Center for Disease Control and Prevention, Guangzhou, China.
authors.forename: Jianyun
authors.initials: J
authors.lastname: Lu
authors.affiliation: Guangzhou Center for Disease Control and Prevention, Guangzhou, China.
authors.forename: Yiyun
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Guangzhou Center for Disease Control and Prevention, Guangzhou, China.
authors.forename: Enjie
authors.initials: E
authors.lastname: Lu
authors.affiliation: Guangzhou Center for Disease Control and Prevention, Guangzhou, China.
authors.forename: Xincai
authors.initials: X
authors.lastname: Xiao
authors.affiliation: Guangzhou Center for Disease Control and Prevention, Guangzhou, China.
authors.forename: Biao
authors.initials: B
authors.lastname: Di
authors.affiliation: Guangzhou Center for Disease Control and Prevention, Guangzhou, China.
authors.forename: Huazhang
authors.initials: H
authors.lastname: Liu
authors.affiliation: Guangzhou Center for Disease Control and Prevention, Guangzhou, China.
authors.forename: Zhicong
authors.initials: Z
authors.lastname: Yang
authors.affiliation: Guangzhou Center for Disease Control and Prevention, Guangzhou, China. Electronic address: wangming@gzcdc.org.cn.
authors.forename: Ming
authors.initials: M
authors.lastname: Wang
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D002681:China / Q000453:epidemiology; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D053118:Influenza A Virus, H1N1 Subtype; D053122:Influenza A Virus, H3N2 Subtype; D009981:Influenza B virus; D007251:Influenza, Human / Q000401:mortality*; D008875:Middle Aged; D015233:Models, Statistical; D062486:Public Health Surveillance; D055815:Young Adult
keywords: Excess deaths; Human; Influenza; Mortality; Regression analysis