我国莱姆病的流行病学和病原学研究

Studies on Epidemiology and Etiology of Lyme Disease in China

1987～1996年对22个省（市、区）的60个县、区进行了莱姆病的调查研究。血清流行病学证实22个省（市、区）林区人群均存在莱姆病感染，感染率平均为5．06％（1724／34104）。病原学证实17个省（市＼区）存在莱姆病自然疫源地。11个省（市、区）有典型病例存在。东北林区患病率为1％～4％。全沟硬蜱是我国北方林区莱姆病螺旋体的主要生物媒介，南方的粒形硬蜱和二棘血蜱在传播中可能起重要作用。姬鼠属可能是莱姆病螺旋体的主要贮存宿主。从病人、蜱或动物中分离出130株莱姆病螺旋体，中国菌株SDS－PAGE蛋白图形、质粒谱和DNA限制性内切酶谱与北美菌株显著不同。rRNA基因多态性分析，中国菌株可被分为三个基因种，其中第一基因种（B．burgdorferisensustricto）在亚洲是首次发现.

From 1987 to 1996, an investigation and study on Lyme disease was conducted in sixty counties and districts of twenty-two provinces (autonomous region, municipality). Seroepidemiological findings indicated that some residents from forest areas of twenty-two provinces had a high antibody titer for Borrelia burgdorferi with positive rate 5.06% (1724/34104). Endemic foci of Lyme disease were discovered in seventeen provinces by etiological evidence. Typical cases of Lyme disease were diagnosed ineleven provinces. Prevalence rate of Lyme disease in forest region of northeast China was 1% - 4%.Ixodes persulcatus played a leading role in the transmission of Borrelia burgdorferi to human in northernpart of China. Ixodes granulatus and Haemaphysalis bispinosa might serve as principal vector of Borreliaburgdorferi in the southern region. Genus apodemus might serve as a major reservoir for B. burgdorferi.A total number of 130 isolates of B. burgdorferi were recovered from patients, ticks or animals. Isolatesfrom China were obviously different from the ones isolated in North America in SDS - PAGE protein profile, plasmid and REA. The analysis of rRNA gene restriction patterns indicated that the Chineseisolates were divided in three genospecies. Genospecies Ⅰ(B. burgdorferi sensu stricto) was firstlydiscovered in Asia.