title: [Typhoid and paratyphoid fever in Yunnan province: distributional patterns and the related meteorological factors].
abstract: OBJECTIVE
  To characterize the spatial distribution of typhoid and paratyphoid fever (TPF) in Yunnan province, China and to determine the effectiveness of meteorological factors on the epidemics of TPF.
  
  
  METHODS
  Data of reported TPF cases in Yunnan province (2001 - 2007) from the China Information System for Diseases Control and Prevention was applied to GIS-based spatial analyses to detect their spatial distribution and clustering of TPF incidence at the county level. Panel data analysis was used to identify the relationships between the TPF incidence and meteorological factors including monthly average temperature, monthly cumulative precipitation and monthly average relative humidity.
  
  
  RESULTS
  During the study period, the average incidence of TPF in Yunnan province was 23.11/100 000, with majority of the TPF cases emerged in summer and autumn. Although widely distributed, two TPF clusters were detected in Yunnan province based on the spatial analysis: one area around Yuxi city with the average annual incidence as 207.45/100 000 and another at the junctions of Yunnan province with Burma and Laos. Based on results from panel data analysis, the incidence of TFP was shown to be associated with meteorological factors such as temperature, precipitation, relative humidity and one month lag of temperature increase [10°C increase in the monthly average temperature: IRR = 1.30 (95%CI: 1.24 - 1.36); 10% increase in monthly average relative humidity: IRR = 1.07 (95%CI: 1.05 - 1.09); 100 mm rise in monthly cumulative precipitation: IRR = 1.02 (95%CI: 1.00 - 1.03); and 10°C average temperature increase, the last month: IRR = 1.73 (95%CI: 1.64 - 1.82)].
  
  
  CONCLUSIONS
  Areas with high TPF incidence were detected in this study, which indicated the key areas for TPF control in Yunnan province. Meteorological factors such as temperature, precipitation and humidity played a role in the incidence of TPF.
authors.affiliation: Institute for Communicable Disease Control and Prevention, State Key Laboratory for Infectious Disease Prevention and Control, Chinese Center for Disease Control and Prevention, Beijing 102206, China.
authors.forename: Lu-Xi
authors.initials: LX
authors.lastname: Wang
authors.forename: Mei-Ying
authors.initials: MY
authors.lastname: Yan
authors.forename: Li-Qun
authors.initials: LQ
authors.lastname: Fang
authors.forename: Xiao-Qing
authors.initials: XQ
authors.lastname: Fu
authors.forename: Duo-Chun
authors.initials: DC
authors.lastname: Wang
authors.forename: Jun-Ling
authors.initials: JL
authors.lastname: Sun
authors.forename: Wu-Chun
authors.initials: WC
authors.lastname: Cao
authors.forename: Jing
authors.initials: J
authors.lastname: Zhang
authors.forename: Biao
authors.initials: B
authors.lastname: Kan
mesh_terms: D002681:China / Q000453:epidemiology; D002980:Climate; D040362:Geographic Information Systems; D006801:Humans; D006813:Humidity; D015994:Incidence; D008685:Meteorological Concepts; D010284:Paratyphoid Fever / Q000453:epidemiology*; D013029:Space-Time Clustering; D013696:Temperature; D014435:Typhoid Fever / Q000453:epidemiology*