江河对云南省德宏州鼠间鼠疫播散的阻隔作用研究

Study on the barrier effect of rivers on the spread of rodent plague in Dehong prefecture of Yunnan province, China

目的探讨江河对鼠间鼠疫播散的阻隔作用。方法收集1982年1月至2007年12月云南省德宏傣族景颇族自治州(德宏州)鼠间鼠疫疫点资料,按年份统计各县(市)和以大盈江、龙川江为界划分的3个区域(国境-大盈江、大盈江-龙川江、龙川江-州界)的鼠间鼠疫所涉及的乡镇和疫点数,根据熵指数计算各县(市)和各区域的流行强度,依据县(市)和区域面积对流行强度校正,用Kruskal-Wallis H法检验县(市)间和区域间校正流行强度的差异。结果 1982-2007年鼠间鼠疫在盈江、梁河、陇川县、瑞丽和芒市分别累计流行16、11、19、11、10年,疫点数分别为159、96、93、76、35个,经检验5个县(市)1982-2007年鼠间鼠疫校正流行强度总体分布差异无统计学意义(H=8.277,P=0.082);而按河流划分区域后,鼠间鼠疫在边境-大盈江、大盈江-龙川江、龙川江-州界区域内分别累计流行16、25、10年,疫点数分别为103、321、35个,经检验各区域流行强度总体分布差异有统计学意义(H=19.738,P=0.000),边境-大盈江与大盈江-龙川江、大盈江-龙川江和龙川江-州界的差别均有统计学意义(χ2=18.423,P=0.003;χ2=26.692,P=0.000)。结论江河对云南省德宏州鼠间鼠疫的播散可能有阻隔作用,可能与江河影响鼠疫耶尔森菌的分布、宿主和媒介的群落、种群与分布相关。

Objective To investigate the barrier effect of rivers on the spread of rodent plague.Methods The data of the rodent plague foci in Dehong autonomous prefecture of Yunnan province,China,from January 1982 to December 2007 were collected.The numbers of townships and plague foci with rodent plague were recorded in each county(city)and in each of the three regions divided by the Daying River and Longchuan River(national borders-Daying River,Daying RiverLongchuan River,and Longchuan River-prefecture borders)in each year.The epidemic intensity values of five counties(cities)and three regions were calculated according to the entropy index and adjusted for area size.The difference in adjusted epidemic intensity between the five counties(cities)or the three regions were analyzed using the Kruskal-Wallis H test.Results During 1982-2007,in Yingjiang,Lianghe,Longchuan,Ruili,and Mangshi,rodent plague was epidemic for16,11,19,11,and 10 years,respectively,and the numbers of plague foci were 159,96,93,76,and 35,respectively.There was no significant difference in the overall distribution of adjusted epidemic intensity between the five counties(H=8.277,P=0.082).In the three regions(national borders-Daying River,Daying River-Longchuan River,and Longchuan Riverprefecture borders),plague was epidemic for 16,25,and 10 years,respectively,and the numbers of plague foci were 103,321,and 35,respectively.There was a significant difference in the overall distribution of adjusted epidemic intensity between the three regions(H=19.738,P=0.000),and significant differences were also observed between the region from Longchuan River to Daying River and the region from national borders to Daying River or the region from Longchuan River to prefecture borders(χ2=18.423,P=0.003;χ~2=26.692,P=0.000).Conclusion Rivers may have a barrier effect on the spread of rodent plague in Dehong prefecture,which may be related to the effects of rivers on the geographical distribution of Yersinia pestis and the community,population and distribution of the host and vector fleas of Y.pestis.