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Genetic diversity and carriage dynamics of Neisseria lactamica in infants

Julia S Bennett1, David T Griffiths, Noel D McCarthy

  • 1The Peter Medawar Building for Pathogen Research and Department of Zoology, University of Oxford, South Parks Rd., Oxford OX1 3SY, United Kingdom.

Infection and Immunity
|March 24, 2005
PubMed

Insights

Neisseria lactamica carriage in infants is genetically diverse and long-lived, with most children carrying only one strain. This understanding is crucial for developing new vaccines against related pathogens like Neisseria meningitidis.

Area of Science:

  • Microbiology
  • Immunology
  • Vaccinology

Background:

  • Neisseria lactamica is a commensal bacterium related to the pathogen Neisseria meningitidis.
  • N. lactamica colonization may confer immunity to meningococcal disease.
  • Understanding N. lactamica carriage dynamics is vital for developing novel vaccines.

Purpose of the Study:

  • To investigate the population diversity and carriage dynamics of Neisseria lactamica in infants.
  • To inform the selection of representative isolates for Neisseria meningitidis vaccine development.

Main Methods:

  • Multilocus sequence typing (MLST) of N. lactamica isolates.
  • Longitudinal carriage studies in infants (n=100 and n=216).
  • Monitoring carriage from early infancy up to 96 weeks of age.

Main Results:

  • High genetic diversity observed, with 69 distinct genotypes from 75 carriers.
  • Carriage was generally long-lived, with a low loss rate (<1% per week).
  • Most infants (72%) carried a single N. lactamica genotype over time.

Conclusions:

  • N. lactamica exhibits significant genetic diversity in infant populations.
  • Long-term carriage of specific genotypes suggests limited strain replacement.
  • Findings impact the strategy for selecting N. lactamica strains for vaccine development against N. meningitidis.

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