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Characterization of Neisseria meningitidis isolates collected from 1974 to 2003 in Japan by multilocus sequence

Hideyuki Takahashi1, Toshiro Kuroki1, Yuko Watanabe1

  • 1Department of Bacteriology, National Institute of Infectious Diseases, Tokyo, Japan 2Department of Microbiology, Kanagawa Prefectural Public Health Laboratory, Chigasaki, Japan 3Department of Bacteriology, Ehime Prefectural Institute of Public Health and Environmental Science, Matsuyama, Japan.

Journal of Medical Microbiology
|June 9, 2004
PubMed

Insights

Japanese Neisseria meningitidis strains show genetic diversity, with some common globally and others unique to Japan. This suggests a mix of international and indigenous clones circulating in Japan.

Area of Science:

  • Microbiology
  • Genetics
  • Epidemiology

Background:

  • Neisseria meningitidis causes meningitis and sepsis globally.
  • Understanding the genetic diversity of meningococcal isolates is crucial for disease control and prevention.

Purpose of the Study:

  • To analyze the genetic characteristics of Neisseria meningitidis strains isolated in Japan over 30 years.
  • To identify global and Japan-specific genetic lineages of Neisseria meningitidis.

Main Methods:

  • Serogroup typing of 182 Neisseria meningitidis isolates.
  • Multilocus Sequence Typing (MLST) to determine sequence types (STs) and clonal complexes.
  • Comparison of identified STs with the global MLST database.

Main Results:

  • Serogroup B was predominant (103 isolates), followed by Y (39) and W135 (1).
  • 65 different sequence types (STs) were identified, with 42 unique to Japan.
  • Japanese isolates clustered into six major clonal complexes, including globally prevalent ones (ST-23, ST-44, ST-32) and a novel indigenous complex (ST-2046).

Conclusions:

  • Neisseria meningitidis isolates in Japan exhibit significant genetic heterogeneity.
  • The meningococcal population in Japan comprises both internationally disseminated clones and unique indigenous lineages.
  • This genetic diversity has implications for surveillance and the development of targeted interventions.

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