The Impact Study And Adaptation Capacity Survey Of Climate Change On Dengue Fever In China

Objective (1) To study the potential geographical distribution in the current climatic situation and project the suitable habitat under RCP4.5, RCP6 and RCP8.5 scenarios in 2030 and 2050, to compare the changes of suitable habitat of Aedes albopictus by climate change. (2) Appraisal of the present to future impact of climate change and climate variability on the transmission of dengue under RCP4.5, RCP6 and RCP8.5 in current situation and 2030,2050, to project the changes of dengue risk area and the transmission intensity and analysis the potential impact of climate change on dengue. (3) To learn the awareness baseline and adaptation capacity of the impact of climate change on dengue fever (DF) in the CDC system and provide a scientific basis for establishing the adaptation mechanism to adapt the effect of climate change on DF.Methods (1) The average monthly maximum temperature, average monthly minimum temperature, monthly precipitation, relative humidity at 9am and 3pm in the current and under RCP4.5, RCP6 and RCP8.5 scenarios in 2030 and 2050 were calculated. Use the compare locations(1 species) function in CLIMEX for Windows 3.0 to adjust the biological parameters of Aedes alhopictus then to project the suitable habitat. (2) We developed a biology-driven model to assess the potential impact of rising temperature on the transmission of schistosomiasis in China basis on the lowest suitable temperature for dengue transmission by the infectious lifespan is greater than 1, to calculate the potential transmission index (PTI) and the average transmission period to predict the dengue epidemic risk map under RCP4.5, RCP6 and RCP8.5 scenarios in 2030 and 2050. (3) Using a stratified and cluster random sampling to choose Guangdong CDC,8 city level and 11 county level CDC to investigate the awareness and adaptation capacity of climate change on DF by face-to-face questionnaire.Results (1) In current climatic condition, the highly suitable habitat of Ae. albopictus is centered in south China covered 269 counties (6085.8 km2). With global climate warming, there are 36 counties (948.2km2),55 counties (1382.5km2) and 88 counties (2029.0km2) would be the additional highly suitable habitat for Aedes albopictus under RCP4.5, RCP6 and RCP8.5 in 2030 respectively; additional 86 counties (2131.4km2),103 counties (2516.6km2) and 115 counties (2791.1km2) would be the highly suitable habitat for Aedes albopictus under RCP4.5, RCP6 and RCP8.5 in 2050 respectively. Under different climatic scenarios, the high suitable habitat ranges expand different, RCP8.5 expand fastest and RCP4.5 is most slow. (2) When survival rate of Aedes albopictus is 0.89, the lowest suitable temperature for dengue transmission is 21 ?, and when PTI?1, there are 12659.6km2 in dengue risk area under current climatic condition. Under RCP4.5 in 2030 and 2050, there are additional 12 counties (272.9km2) and 40 counties(691.2km2) would be the dengue risk area; under RCP6 in 2030 and 2050, there are additional 28 counties (505.5km2) and 62 counties(1136.7km2) would be the dengue risk area; and under RCP8.5 in 2030 and 2050, there are additional 88 counties (1602.9km2) and 128 counties(2394.4km2) would be the dengue risk area. The highly suitable habitat for Aedes albopictus and dengue risk areaa were consitently in the same scenarioes same year. (3) 424 (98.6%) questionnaires are valid. The awareness about the impact of climate change on DF are significantly different in age, educational background, title, institute level and the local incidence of DF in the staff of Guangdong CDC system, the awareness levels correlate with educational background, institute level and the local dengue incidence, the regression equation is y=11.093+0.556x1+1.790 X2+1.040 X3(x1 is dengue incidence, X2 is educational background, X3 is institute level); The adaptation capacity of climate change on DF are significantly different in age, sex, title, educational background, institute level, the local incidence of DF and whether he occupies dengue control and prevention, the adaptation capacity levels correlate with the local incidence of DF, whether he occupies dengue control and prevention, awareness level, the regression equation is y=12.238+1.418x1-2.637x2+0.242X3(X1 is dengue incidence, X2 is whether he/she occupies dengue control and prevention, X3 is awareness level). When regard the individual from one institute as one unit to calculate the average awareness and adaptation capacity, the adaptation capacity levels of institutes are significantly different with the local economic. The main approach that Guangdong CDC staff obtain the information about climate change on the health are internet, television, newspapers and magazines.Conclusion (1) The expanding of suitable habitat range for Aedes albopictus would affect the dengue risk area and epidemic pattern, we should strengthen surveillance for Aedes albopictus and dengue and build the effective early-warning system to prevent and control dengue outbreak. (2) With global warming, the dengue epidemic area in China will expand the range from south to north, non-epidemic area would become the epidemic area and epidemic area would become endemic. We should strengthen the dengue surveillance and adaptation. (3) The awareness levels about the impact of climate change on DF in Guangdong CDC system staff are mainly correlated with educational background, the local incidence of DF and the local economy, but the adaptation capacity is only associated with economics.