不同气候变化情景下中国血吸虫病传播的范围与强度预测 Projection of transmission scale and intensity of schistosomiasis in China under climate change scenarios 杨 坤1 潘 婕2 杨国静1 李石柱3 许吟隆2 周晓农3* 1 江苏省血吸虫病防治研究所,无锡 214064;2 中国农业科学院农业环境与可持续发展研究所/农业部农业环境与气候变化重点开放实验室,北京 10008;3 中国疾病预防控制中心寄生虫病预防控制所,上海 200025
内容/Content 模型构建的生物学基础 The biological parameter 气候变化预测模型 Climate change scenarios 模型的构建 Modeling building 预测图 Prediction maps
Distribution of schistosomiasis in China in 2006 Among 448 counties of 12 provinces as original endemic areas in China, 271 (60.49%) counties reached the criteria of transmission interruption, 71 (15.85%) counties reached the criteria of transmission controlled, and 105 (23.44%) counties are still in the transmission status. Distribution of schistosomiasis in China in 2006
血吸虫与钉螺的生物学参数 The biological parameters of Schistosoma japonicum and Oncomelania hupensis
钉螺发育积温计算 Accumulated degree-days for O.hupensis The lowest temperature for snail death = -2.72 ℃, The temperature for 50% of snail presenting hibernation = 5.87 ℃ ADDO.h= 3846.28±32.59 (℃ · d) Tmin of snail death accumulated degree-days (ADD) T0 for snail development Accumulated days (D) Ta for snail aestivation Tmax of snail death The highest temperature for snail death = 42.13 ℃ The highest temperature for snail presenting aestivation at 40 ℃ - 92.22% snail
血吸虫发育积温计算 Accumulated degree-days for S. japonicum The lowest temperature for S.j. development in Oncomelania snail = 15.35±1.30℃。 ADDS.j= 842.95±70.71 ( ℃ · d) accumulated degree-days (ADD) The lowest temperature for S.j. developing in snail (T0) Accumulated days (D) In the endemic region
气候变化情景模型→气候因子数据 climate change scenarios →data 选用由英国Hadley中心开发的区域气候模型PRECIS(Predict Regional Climate for Impact Assessment) 。 分别选取中-高气体排放(A2)和中-低气体排放(B2)两种气体排放情景,A2情景为CO2约1 %的高排放, B2情景为CO2约0. 5 %的低排放。 在两种气体排放情景下,以区域气候模型(RCM)的外部趋动,模拟出我国区域内50Km×50Km网格的逐日最高气温、最低气温、降水、辐射等20余项气象指标,其中RCM模拟的1961-1990年历年的逐日最高气温、最低气温、降水和辐射等气象信息为基准时段(BS),代表当前的基础气候数据。
血吸虫传播模型 The transmission models 模型的构建主要考虑血吸虫病的传播媒介-钉螺与病原体-血吸虫两方面,分别以钉螺温度-生存模型和血吸虫扩散模型,预测钉螺分布区域变化和血吸虫传播指数变化。 The transmission models including the two apartments, namely transmission scale and transmission index models, predict the change of potential transmission area and transmission index.
钉螺温度-生存模型 transmission scale model 利用钉螺的发育有效积温、极端温度(最高与最低致死温度)等参数,构建温度-钉螺生存模型,确定钉螺的分布与扩散范围 Using three parameters, namely, the accumulated degree-days (ADD), minimum and maximum temperature for O.hupensis to build the transmission scale model
血吸虫气候-扩散模型 transmission index model 血吸虫的气候-扩散模型包括两部分,一是GDD1,即血吸虫在钉螺体内的发育有效积温;二是GDD2,即当雨量超过了蒸发量和地表25mm土层吸水能力时造成土壤表面有积水时, 虫体可以逸出螺体向外扩散的传播指数。因温度、降雨及地表积水的变化对血吸虫的扩散存在延迟现象,因此本模型的构建采用10天为时间单位 Transmission index model include two apartments, S. japonicum can survive in snail (GDD1)and S. japonicum release from snail(GDD2) 传播指数(transmission index)=GDD1+GDD2
气候-疾病传播模型 Climate change-disease transmission model 气象数据输出: A2、B2下2046年至2050年(2050年时段)和2066年至2070年(2070年时段) Climate data export: The 2050s and 2070s under A2、B2 钉螺分布与血吸虫传播指数 Transmission scale and index GIS制图 GIS maping 模型拟合度验证 Modeling validate 计算变化 Calculate change
Transmission scale change under A2 Transmission scale of 2050s under A2 scenarios A2下2070年时段传播范围Transmission scale of 2070s under A2 scenarios 潜在流行区北移扩散面积分别41.5万平方公里 潜在流行区北移扩散面积76.9万平方公里。
Transmission scale change under B2 Transmission scale of 2050s under B2 scenarios B2下2070年时段传播范围Transmission scale of 2070s under B2 scenarios 潜在流行区北移扩散面积分别35.2万平方公里 潜在流行区北移扩散面积46.4万平方公里。
Transmission index change under A2 Transmission intensity of 2050s under A2 scenarios A2下2070年时段传播指数Transmission intensity of 2070s under A2 scenarios 传播指数在1500以上的高风险区域较2005年增加了89.569% 传播指数在1500以上的高风险区域较2005年增加了155.026%。
Transmission index change under B2 Transmission intensity of 2050s under A2 scenarios B2下2070年时段传播指数Transmission intensity of 2070s under A2 scenarios 传播指数在1500以上的高风险区域较2005年增加了81.302% 传播指数在1500以上的高风险区域较2005年增加了136.837 %。
谢 谢 18