Open AccessOutbreak of W135 Meningococcal Disease in 2000: Not Emergence of a New W135 Strain but Clonal Expansion within the Electophoretic Type–37 Complex
Author(s) -
Leonard W. Mayer,
Michael Reeves,
Nasser Al-Hamdan,
Cláudio Tavares Sacchi,
MuhamedKheir Taha,
Gloria W. Ajello,
Susanna Schmink,
Corie Noble,
M. Lucia Tondella,
Anne M. Whitney,
Yagoub Al-Mazrou,
Mohammed Al-Jefri,
Amin Mishkhis,
Sameer Sabban,
Dominique A. Caugant,
Jairam R. Lingappa,
Nancy E. Rosenstein,
Tanja Popović
Publication year - 2002
Publication title -
the journal of infectious diseases (online. university of chicago press)/the journal of infectious diseases
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.69
H-Index - 252
eISSN - 1537-6613
pISSN - 0022-1899
DOI - 10.1086/340414
Subject(s) - outbreak , clone (java method) , subtyping , neisseria meningitidis , biology , virology , meningococcal disease , genotype , strain (injury) , microbiology and biotechnology , genetics , bacteria , gene , anatomy , computer science , programming language
In 2000, >400 cases of disease caused by Neisseria meningitidis serogroup W135 (MenW135), the largest MenW135 outbreak reported to date, occurred worldwide among Hajj pilgrims and their contacts. To elucidate the origin of the outbreak strains and to investigate their relatedness to major clonal groups, genotypic and phenotypic subtyping was performed on 26 MenW135 outbreak-associated isolates and 50 MenW135 isolates collected worldwide from 1970 through 2000. All outbreak-associated isolates were members of a single clone of the hypervirulent electrophoretic type (ET)-37 complex, designated the "(W)ET-37 clone"; 19 additional MenW135 strains were also members of this clone, and the remaining 31 MenW135 strains were clearly distinct. The 2000 MenW135 outbreak was not caused by emergence of a new MenW135 strain but rather by expansion of the (W)ET-37 clone that has been in circulation at least since 1970; the strains most closely related to those causing the 2000 outbreak have been isolated in Algeria, Mali, and The Gambia in the 1990s.