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Updated: May 30, 2026
10:19
A Murine Model of Group B Streptococcus Vaginal Colonization
Published on: November 16, 2016
Genetic differences between invasive and noninvasive neonatal group B streptococcal isolates.
Kirsten Fluegge1, Juliana Wons, Barbara Spellerberg
1Center for Pediatrics and Adolescent Medicine, University Medical Center Freiburg, Freiburg, Germany.
The Pediatric Infectious Disease Journal
|July 22, 2011
Summary
Group B Streptococcus (GBS) strains causing neonatal sepsis are less diverse than non-invasive strains, suggesting virulent GBS are selected during infection. Understanding GBS diversity is key to preventing neonatal disease.
Area of Science:
- Microbiology
- Infectious Diseases
- Neonatal Health
Background:
- Streptococcus agalactiae, or group B Streptococcus (GBS), is a leading cause of neonatal sepsis and meningitis.
- Understanding GBS clonal relatedness and diversity is crucial for elucidating neonatal GBS sepsis pathogenesis.
Purpose of the Study:
- To investigate the molecular diversity and clonal relatedness of invasive and non-invasive GBS isolates from neonates.
- To compare genetic profiles of GBS strains causing sepsis versus those found in neonates with suspected sepsis but negative blood cultures.
Main Methods:
- Comparative analysis of invasive and non-invasive GBS isolates from a German study cohort.
- Techniques included pulsed-field gel electrophoresis (PFGE), surface protein gene profiling, and multilocus sequence typing (MLST).
- MLST was specifically applied to serotype III isolates, the most frequent invasive type.
Main Results:
- Non-invasive GBS isolates exhibited significantly greater molecular diversity (PFGE patterns) than invasive isolates.
- Surface protein gene profiling revealed distinct distribution patterns between invasive and non-invasive GBS.
- While sharing clonal complexes, invasive serotype III strains predominantly featured ST-17, whereas non-invasive strains were dominated by ST-389.
Conclusions:
- Neonatal non-invasive GBS strains display substantial molecular diversity.
- Invasive GBS strains appear to be a selected subset of the broader non-invasive GBS population.
- Findings suggest a selection mechanism favoring more virulent GBS strains during the process of neonatal invasion and sepsis development.
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