title: Pneumonia and influenza hospitalizations among children under 5 years of age in Suzhou, China, 2005-2011.
abstract: The disease burden of influenza among children in China has not been well described.
  
  
  
  To estimate the influenza-associated excess hospitalization rate and compare the hospitalization length and costs between pneumonia and influenza (P&I) and other community-acquired diseases (CAD) in Suzhou, China.
  
  
  
  We retrospectively collected hospital discharge data on pediatric patients' discharge diagnosis, hospital costs, and length of hospital stay in Suzhou. P&I hospitalization was defined as a primary discharge diagnosis of pneumonia and influenza disease (ICD-10 codes J09-J18). Other CAD were common community-acquired diseases among children. Negative binomial regression models were used to estimate the weekly P&I hospitalizations in Suzhou. Excess P&I hospitalizations due to influenza were calculated as the difference in P&I hospitalizations between the epidemic period and the baseline period. Baseline was defined as when the influenza-positive rates were <5% for two consecutive weeks.
  
  
  
  From October 2005 to September 2011, we identified a total of 180 091 all-cause hospitalizations among children <5 years of age in Suzhou City. The rates of P&I and influenza-associated excess hospitalizations were highest in the 2009-2010 pandemic and 2010-2011 post-pandemic seasons. Infants <6 months of age had the highest P&I hospitalization rates, the longest hospital stays (7.5-8.0 days), and the highest hospitalization costs for P&I. Compared with other CAD, children admitted for P&I had longer hospital stays and higher hospitalization costs.
  
  
  
  The influenza-associated P&I hospitalization rates and economic burden were high among children. Targeted influenza prevention and control strategies for young children in Suzhou may reduce the influenza-associated hospitalizations in this age group.
authors.affiliation: Department of Epidemiology, School of Public Health, Fudan University, Shanghai, China.|Key Laboratory of Public Health Safety, Ministry of Education, Shanghai, China.|Collaborative Innovation Center of Social Risks Governance in Health, Shanghai, China.
authors.forename: Xiyan
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Suzhou Center for Disease Prevention and Control, Suzhou, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Suzhou Center for Disease Prevention and Control, Suzhou, China.
authors.forename: Liling
authors.initials: L
authors.lastname: Chen
authors.affiliation: Division of Infectious Disease, Chinese Center for Disease Control and Prevention, Beijing, China.
authors.forename: Luzhao
authors.initials: L
authors.lastname: Feng
authors.affiliation: Division of Infectious Disease, Chinese Center for Disease Control and Prevention, Beijing, China.
authors.forename: Hongjie
authors.initials: H
authors.lastname: Yu
authors.affiliation: Department of Epidemiology, School of Public Health, Fudan University, Shanghai, China.|Key Laboratory of Public Health Safety, Ministry of Education, Shanghai, China.|Collaborative Innovation Center of Social Risks Governance in Health, Shanghai, China.
authors.forename: Genming
authors.initials: G
authors.lastname: Zhao
authors.affiliation: Department of Epidemiology, School of Public Health, Fudan University, Shanghai, China.|Key Laboratory of Public Health Safety, Ministry of Education, Shanghai, China.|Collaborative Innovation Center of Social Risks Governance in Health, Shanghai, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Zhang
mesh_terms: D002675:Child, Preschool; D002681:China / Q000453:epidemiology; D017281:Cost of Illness; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data*; D006801:Humans; D007223:Infant; D007251:Influenza, Human / Q000150:complications / Q000453:epidemiology* / Q000821:virology; D008297:Male; D058873:Pandemics; D011014:Pneumonia / Q000453:epidemiology*; D012189:Retrospective Studies; D012621:Seasons
keywords: China; children; hospitalization; influenza; pneumonia 