Hansen Søren Mose, Uldbjerg Niels, Kilian Mogens, Sørensen Uffe B Skov
Department of Medical Microbiology and Immunology, The University of Aarhus, DK-8000 Aarhus C, Denmark.
J Clin Microbiol. 2004 Jan;42(1):83-9. doi: 10.1128/JCM.42.1.83-89.2004.
The population dynamics of Streptococcus agalactiae (group B streptococci [GBS]) colonization of the vagina and anorectal area was investigated in a cohort of 77 Danish women during and after their pregnancy by a new sensitive method. The mean carriage rate among individual observations was 36%, and the cumulative carriage rate over the entire observation period was 54%. Examination of more than 1500 GBS isolates by pulsed-field gel electrophoresis demonstrated that the GBS population was remarkably homogeneous and stable in each carrier. Virtually all carriers were colonized by a single GBS clone on all occasions spanning up to 2 years. Repeated detection of the same clone even in women who were recorded as intermittent carriers suggests that the actual carrier rate exceeds 50% but that fluctuations in the GBS proportions of the flora occasionally preclude their detection. Newborns and young infants usually carried the same GBS clone as their mothers. However, only twice were identical clones of GBS detected in different women in contrast to the observed clonal relationships of clinical isolates. These observations strongly suggest differences in the properties and epidemiology of virulent GBS clones compared to clones commonly carried by healthy individuals.
采用一种新的敏感方法，对77名丹麦女性在孕期及产后阴道和肛门直肠区域无乳链球菌（B组链球菌[GBS]）定植的群体动态进行了研究。个体观察中的平均携带率为36%，整个观察期内的累积携带率为54%。通过脉冲场凝胶电泳对1500多株GBS分离株进行检测，结果表明GBS群体在每个携带者中非常均一且稳定。实际上，所有携带者在长达2年的所有时间里均由单一GBS克隆定植。即使在记录为间歇性携带者的女性中也反复检测到相同克隆，这表明实际携带率超过50%，但菌群中GBS比例的波动偶尔会妨碍其检测。新生儿和幼儿通常携带与母亲相同的GBS克隆。然而，与临床分离株观察到的克隆关系不同，仅在两名不同女性中检测到相同的GBS克隆。这些观察结果强烈表明，与健康个体通常携带的克隆相比，有毒GBS克隆在特性和流行病学方面存在差异。
