中国莱姆病螺旋体主要生物媒介的调查研究

为研究中国莱姆病螺旋体的生物媒介———蜱的种类、带菌状况及在传播莱姆病中的作用 ,采用布旗法和动物诱捕法在山林地区采集蜱 ,进行分类鉴定 ,应用直接荧光抗体染色法查蜱中肠带菌率 ,BSK培养基分离病原体 ,单克隆抗体鉴定菌株。调查蜱叮咬率与人群莱姆病感染率、患病率以及蜱的季节消长与莱姆病慢性游走性红斑 (ECM )病例发生的季节性关系。在全国 2 0个省 (市、区 )共采集到170 0 0多只蜱 ,分属为 2科 8属 2 3种 ,蜱类分布的地区差异较大 ,北方林区以全沟硬蜱为优势种 ,南方则以二棘血蜱和粒形硬蜱为优势种。 9种蜱的中肠携带莱姆病螺旋体 ,其带菌率以全沟硬蜱、二棘血蜱和粒形硬蜱为高 ,分别为 2 0 .0 0 %～ 4 5.0 0 %、16.0 0 %～ 4 0 .0 0 %和 2 4 .0 0 %。从 8种蜱分离出 10 8株莱姆病螺旋体 ,其单克隆抗体反应与美国B31菌株有明显的差异 ,绝大多数中国菌株对H6831呈阴性反应。蜱叮咬率高的人群 ,莱姆病的感染率和患病率也高。全沟硬蜱的季节消长与ECM发生的季节性相一致。证实多种蜱的中肠内携带莱姆病螺旋体 ;我国北方林区莱姆病螺旋体的主要生物媒介是全沟硬蜱 ,南方林区二棘血蜱和粒形硬蜱是重要的生物媒介。

Investigation on Primary Vectors of Borrelia Burgdorferi in China

From 1987 to 1997,primary vectors of borrelia burgdorferi sensu lato(B.b.s.l.) were investigated in China. A total number of 17 000 ticks collected from 20 provinces, city and autonomous region were classified,including 2 families 8 genus 23 species. There were 108 isolates of B.b.s.l. discovered from 8 species of ticks , including Ixodes persulcatus,I.granulatus, I.acutitarsus, Haemaphysalis concinna, H.longicornis, H.bispinosis, H.cornigera taiwana and Dermacentor silvarum. Ixodes persulcatus was found as the dominant species, accounted for more than 80% of the total number of collected ticks. 20 to 45 per cent adult Ixodes persulcatus contained spirochetes as determined by direct immunofluorescence in the northeast and northwest areas. Seasonal change of adult Ixodes persulcatus was coincident with patients with erythema chronicum migrans. These studies proved that Ixodes persulcatus played a leading role in the transmission of B.b.s.l. to human being in northern region of China. Haemaphysalis bispinosis and Ixodes granulatus were identified as the dominant species with 16 to 40 per cent adult Haemaphysalis bispinosis and 24% per cent adult Ixodes granulatus containing spirochetes as determined by direct immunofluorescence in the southern region of China. Haemaphysalis bispinosis and Ixodes granulatus were proved to be important vectors of B.b.s.l. in the southern area of China.