title: [Analysis on the relationship between malaria epidemics and NOAA-AVHRR NDVI in Hainan province].
abstract: OBJECTIVE
  To explore the relationship between malaria epidemics and NOAA-AVHRR NDVI.
  
  
  METHODS
  Data on malaria were collected in all 19 counties in Hainan province from Feb, 1995 to Jan, 1996. Values regarding normalized difference vegetation index (NDVI)-related indicators including mean and maximum values of NDVI, the area proportion of NDVI values of 145- and 145+, months with NDVI values of 135+, 140+, 145+, 150+ of these counties in this period were all extracted from NOAA-AVHRR images, using ERDAS8.5 software. The coefficients of correlation of malaria incidences and these NDVI-related indicator values were then calculated with SPSS 11.0.
  
  
  RESULTS
  The incidence of malaria showed positive correlations to mean and maximum values of NDVI, the area proportion of NDVI values of 145+ and months with NDVI values of 135+, 140+, 145+, 150+ respectively, but having negative correlation to the area of NDVI values of 145-. The malaria epidemic regions were in accordance with those regions that the NDVI values of 145+ were continuing for 9 months or more.
  
  
  CONCLUSIONS
  Malaria prevalence was associated with NOAA-AVHRR NDVI value which could be considered to be use for malaria surveillance in Hainan province.
authors.affiliation: Department of Epidemiology, Faculty of Preventive Medicine, Fourth Military Medical University, Xi'an 710032, China.
authors.forename: Liang
authors.initials: L
authors.lastname: Wen
authors.forename: De-zhong
authors.initials: DZ
authors.lastname: Xu
authors.forename: Shan-qing
authors.initials: SQ
authors.lastname: Wang
authors.forename: Cai-xu
authors.initials: CX
authors.lastname: Li
authors.forename: Zhi-ying
authors.initials: ZY
authors.lastname: Zhang
authors.forename: Yong-qiang
authors.initials: YQ
authors.lastname: Su
mesh_terms: D000818:Animals; D000852:Anopheles / Q000254:growth & development*; D002681:China / Q000453:epidemiology; D002980:Climate; D004463:Ecology; D017753:Ecosystem; D004784:Environmental Monitoring; D062665:Epidemiological Monitoring; D006801:Humans; D015994:Incidence; D008288:Malaria / Q000453:epidemiology*; D063245:Plant Development; D017215:Satellite Communications; D012621:Seasons