Intercontinental spread of a genetically distinctive complex of clones of Neisseria meningitidis causing epidemic disease.

Abstract

Strains of Neisseria meningitidis responsible for an epidemic of meningococcal disease occurring in Norway since the mid-1970s and for recent increases in the incidence of disease in several other parts of Europe have been identified by multilocus enzyme electrophoresis as members of a distinctive group of 22 closely related clones (the ET-5 complex). Clones of this complex have also colonized South Africa, Chile, Cuba, and Florida, where they have been identified as the causative agents of recent outbreaks of meningococcal disease. There is strong circumstantial evidence that outbreaks of disease occurring in Miami in 1981 and 1982 were caused in large part by bacteria that reached Florida via human immigrants from Cuba.

Targeted vaccination with meningococcal polysaccharide vaccine in one district of the Czech Republic

“…This agrees well with a recent report from Canada, where the identical clone of Neisseria meningitidis C appeared [7]. Targeted meningococcal vaccination Neisseria meningitidis strains were designated on the basis of distinctive combinations of alleles over 13 enzyme loci, as previously described [38,39].…”

Structure and function of repetitive sequence elements associated with a highly polymorphic domain of the Neisseria meningitidis PilQ protein

“…1B and C (Table 2). Strains belonging to the ET-5 clone complex (Caugant et al, 1986), for example, carried either five (R1908), six (7/88) or seven (44/76) copies of the element and strains belonging to cluster A4 carried either four (B4045) or five (BB333) copies.…”

Molecular epidemiology of recent United Kingdom isolates ofNeisseria meningitidisserogroup C

“…Strains in the ET-37 complex have been responsible for the majority of endemic serogroup C disease in the 1980's in the United States [27] and Italy [28]. They were the second most common isolates from cases in Canada [29] and Norway [6]. Strains belonging to this complex have been isolated world-wide during single-clone outbreaks and may form a minor part of outbreaks caused by other meningococci [26].…”

“…Serogroup C organisms are responsible for sporadic and endemic disease, being intermediate between genetically diverse serogroup B meningococci and the relative genetic and antigenic stability of clones of serogroup A [5,6]. In the UK, serogroup C meningococci are also responsible for epidemics and their frequency seems to be increasing [7].…”

“…Techniques used include serogrouping, serotyping, and serosubtyping, MLEE and electropherotyping. The results of some of these techniques have been used to support the hypothesis that N. meningitidis has a clonal population structure [6,[8][9][10]. Serological classification is phenotypically based and suffers from the deficiency that groupings based on it may contain strains that are genotypically dissimilar.…”