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A Murine Model of Group B Streptococcus Vaginal Colonization
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A Murine Model of Group B Streptococcus Vaginal Colonization

Published on: November 16, 2016

Dynamics of Streptococcus agalactiae colonization in women during and after pregnancy and in their infants

Søren Mose Hansen1, Niels Uldbjerg, Mogens Kilian

  • 1Department of Medical Microbiology and Immunology, The University of Aarhus, DK-8000 Aarhus C, Denmark.

Journal of Clinical Microbiology
|January 13, 2004
PubMed

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.

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