Antimeningococcal herd immunity in the Czech Republic--influence of an emerging clone, Neisseria meningitidis ET-15/37

Epidemiol Infect. 1999 Oct;123(2):193-200. doi: 10.1017/s095026889900285x.


For many years, invasive meningococcal disease in the Czech Republic occurred sporadically and was caused mainly by meningococci of serogroup B. In 1993, when a new clone (ET-15/37) emerged, the only phenotype found was C:2a:P1.2,5. In 1995, an antigenic variation of the ET-15/37 clone, B:2a:P1.2,5, occurred. The results of immunological surveys conducted in 1989 and 1996 were compared. A significantly higher proportion of 1996 sera than those collected in 1989 showed bactericidal antibodies against N. meningitidis B:2a:P1.2,5 (19.7 vs. 5.1%) and N. meningitidis C:2a:P1.2,5 (15.9 vs. 7.4%), consistent with increased herd immunity due to the spread of the new clone in the Czech Republic. There were differences in the age distribution of the positive sera.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Age Distribution
  • Age Factors
  • Antigens, Bacterial / blood
  • Carrier State
  • Child
  • Child, Preschool
  • Czech Republic / epidemiology
  • Humans
  • Immunity, Innate
  • Infant
  • Meningococcal Infections / epidemiology*
  • Meningococcal Infections / immunology*
  • Middle Aged
  • Neisseria meningitidis / classification*
  • Neisseria meningitidis / immunology
  • Phenotype
  • Prevalence
  • Seroepidemiologic Studies


  • Antigens, Bacterial