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The duality of virulence and transmissibility in Neisseria meningitidis

Muhamed-Kheir Taha1, Ala-Eddine Deghmane, Aude Antignac

  • 1Unité des Neisseria and Centre National de Référence des Méningocoque, Institut Pasteur, Paris, France. mktaha@pasteur.fr

Trends in Microbiology
|August 6, 2002
PubMed

Insights

Neisseria meningitidis, a common bacterium, shows significant variation. Frequent genetic changes in these meningococcal populations explain their diversity and evolutionary success in humans.

Area of Science:

  • Microbiology
  • Bacterial Pathogenesis
  • Evolutionary Biology

Background:

  • Neisseria meningitidis is a human nasopharyngeal commensal.
  • Carriage strains are heterogeneous and transmitted between carriers.
  • Invasive disease is caused by distinct virulent strains, separate from the carrier transmission cycle.

Purpose of the Study:

  • To investigate the heterogeneity and variability of Neisseria meningitidis populations.
  • To understand the generation of variants affecting virulence and transmissibility.
  • To explain the evolutionary success of this human-restricted bacterium.

Main Methods:

  • Population genetics analysis of carriage strains.
  • Genomic characterization of virulent and commensal isolates.
  • Comparative analysis of virulence and transmissibility factors.

Main Results:

  • Neisseria meningitidis populations in carriers are highly heterogeneous.
  • Frequent generation of variants with altered virulence and/or transmissibility was observed.
  • These variations are not part of the disease transmission cycle.

Conclusions:

  • The continuous generation of variants contributes to meningococcal population diversity.
  • Bacterial variability is a key factor in the evolutionary success of Neisseria meningitidis.
  • Understanding these dynamics is crucial for controlling meningococcal disease.

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