Peavey C A, Lane R S
Department of Environmental Science, Policy & Management, University of California, Berkeley 94720, USA.
J Clin Microbiol. 1996 Jan;34(1):71-5. doi: 10.1128/jcm.34.1.71-75.1996.
The infectivity and dissemination to the skin of six isolates of Borrelia burgdorferi were evaluated by inoculating them into groups of deer mice (Peromyscus maniculatus), hamsters, and Swiss Webster mice. Rodent infection was assayed by culture of ear punch biopsy specimens taken at 4, 8, and 12 weeks postinoculation (p.i.). Spirochetes were detected in biopsy specimens from individuals of all three host species that had been inoculated with four isolates (CA3, CA4, CA7, and CA8). Ear punch biopsy specimens taken from Swiss Webster mice at 12 weeks p.i. yielded an additional reisolate (CA2), even though these animals did not seroconvert. The remaining isolate (CA9) was not recovered from any host. However, two deer mice and all hamsters and Swiss Webster mice inoculated with CA9 seroconverted. All six isolates were of low infectivity to ticks when inoculated intramuscularly into hosts. Only 4 (1.6%) of 250 Ixodes pacificus larvae acquired and transstadially maintained infection from hosts inoculated intramuscularly. Infectivity of three isolates for ticks also was tested in Swiss Webster mice injected intradermally. The mean prevalences of infection in xenodiagnostic ticks fed on these mice at 4 weeks p.i. were 47.9, 1.2, and 2.2% for isolates CA4, CA7, and CA8, respectively. The mean prevalences of infection for ticks fed on the same mice at 12 weeks p.i. were 36.4, 11.8, and 20.4%, respectively. Such differences in the infectivity and rate of dissemination of individual isolates of B. burgdorferi should be considered during studies of reservoir and vector competence.
通过将6株伯氏疏螺旋体接种到多组鹿鼠（白足鼠）、仓鼠和瑞士韦伯斯特小鼠体内，评估其传染性及向皮肤的传播情况。通过对接种后4周、8周和12周采集的耳打孔活检标本进行培养来检测啮齿动物的感染情况。在接种了4株菌株（CA3、CA4、CA7和CA8）的所有三种宿主物种个体的活检标本中均检测到了螺旋体。在接种后12周从瑞士韦伯斯特小鼠采集的耳打孔活检标本中又分离出了一株菌株（CA2），尽管这些动物未发生血清转化。其余菌株（CA9）未从任何宿主中分离出来。然而，接种CA9的两只鹿鼠以及所有仓鼠和瑞士韦伯斯特小鼠均发生了血清转化。将所有6株菌株肌肉注射到宿主体内时，它们对蜱的传染性均较低。250只太平洋硬蜱幼虫中只有4只（1.6%）从肌肉注射接种的宿主中获得并经变态发育维持了感染。还在皮内注射的瑞士韦伯斯特小鼠中测试了3株菌株对蜱的传染性。在接种后4周以这些小鼠为食的异种诊断蜱中的平均感染率，菌株CA4、CA7和CA8分别为47.9%、1.2%和2.2%。在接种后12周以同一批小鼠为食的蜱中的平均感染率分别为36.4%、11.8%和20.4%。在研究宿主和媒介能力时，应考虑伯氏疏螺旋体各菌株在传染性和传播速率方面的此类差异。
