title: Regional impact of climate on Japanese encephalitis in areas located near the three gorges dam.
abstract: BACKGROUND
  In this study, we aim to identify key climatic factors that are associated with the transmission of Japanese encephalitis virus in areas located near the Three Gorges Dam, between 1997 and 2008.
  
  
  METHODS
  We identified three geographical regions of Chongqing, based on their distance from the Three Gorges Dam. Collectively, the three regions consisted of 12 districts from which study information was collected. Zero-Inflated Poisson Regression models were run to identify key climatic factors of the transmission of Japanese encephalitis virus for both the whole study area and for each individual region; linear regression models were conducted to examine the fluctuation of climatic variables over time during the construction of the Three Gorges Dam.
  
  
  RESULTS
  Between 1997 and 2008, the incidence of Japanese encephalitis decreased throughout the entire city of Chongqing, with noticeable variations taking place in 2000, 2001 and 2006. The eastern region, which is closest to the Three Gorges Dam, suffered the highest incidence of Japanese encephalitis, while the western region experienced the lowest incidence. Linear regression models revealed that there were seasonal fluctuations of climatic variables during this period. Zero-Inflated Poisson Regression models indicated a significant positive association between temperature (with a lag of 1 and 3 months) and Japanese encephalitis incidence, and a significant negative association between rainfall (with a lag of 0 and 4 months) and Japanese encephalitis incidence.
  
  
  CONCLUSIONS
  The spatial and temporal trends of Japanese encephalitis incidence that occurred in the City of Chongqing were associated with temperature and rainfall. Seasonal fluctuations of climatic variables during this period were also observed. Additional studies that focus on long-term data collection are needed to validate the findings of this study and to further explore the effects of the Three Gorges Dam on Japanese encephalitis and other related diseases.
authors.affiliation: Division of Environmental Health Sciences, College of Public Health, The Ohio State University, Columbus, Ohio, United States of America.
authors.forename: Yuntao
authors.initials: Y
authors.lastname: Bai
authors.affiliation: Department of Statistics, The Ohio State University, Columbus, Ohio, United States of America.
authors.forename: Zhiguang
authors.initials: Z
authors.lastname: Xu
authors.affiliation: Key Laboratory of Surveillance and Early-Warning on Infectious Disease, Chinese Center for Disease Control and Prevention, Beijing, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Chongqing Center for Disease Control and Prevention, Chongqing, China.
authors.forename: Deqiang
authors.initials: D
authors.lastname: Mao
authors.affiliation: Wanzhou District Control of Diseases Prevention and Control, Chongqing, China.
authors.forename: Chao
authors.initials: C
authors.lastname: Luo
authors.affiliation: Yichang Center for Disease Control and Prevention, Yichang, Hubei Province, China.
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: He
authors.affiliation: State Key Laboratory for Infectious Diseases Prevention and Control, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China.
authors.forename: Guodong
authors.initials: G
authors.lastname: Liang
authors.affiliation: Division of Biostatistics, College of Public Health, The Ohio State University, Columbus, Ohio, United States of America.
authors.forename: Bo
authors.initials: B
authors.lastname: Lu
authors.affiliation: Division of Environmental Health Sciences, College of Public Health, The Ohio State University, Columbus, Ohio, United States of America.
authors.forename: Michael S
authors.initials: MS
authors.lastname: Bisesi
authors.affiliation: Division of Environmental Health Sciences, College of Public Health, The Ohio State University, Columbus, Ohio, United States of America.
authors.forename: Qinghua
authors.initials: Q
authors.lastname: Sun
authors.affiliation: Department of Statistics, The Ohio State University, Columbus, Ohio, United States of America.
authors.forename: Xinyi
authors.initials: X
authors.lastname: Xu
authors.affiliation: Key Laboratory of Surveillance and Early-Warning on Infectious Disease, Chinese Center for Disease Control and Prevention, Beijing, China.
authors.forename: Weizhong
authors.initials: W
authors.lastname: Yang
authors.affiliation: Key Laboratory of Surveillance and Early-Warning on Infectious Disease, Chinese Center for Disease Control and Prevention, Beijing, China ; Department of Vector Biology and Control, State Key Laboratory for Infectious Diseases Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China.
authors.forename: Qiyong
authors.initials: Q
authors.lastname: Liu
mesh_terms: D002681:China / Q000453:epidemiology; D002980:Climate; D004672:Encephalitis, Japanese / Q000453:epidemiology* / Q000635:transmission; D004777:Environment; D005843:Geography; D006801:Humans; D015994:Incidence; D012307:Risk Factors; D012621:Seasons; D062211:Spatio-Temporal Analysis