REVIEW ARTICLE Molecular typing methods for Neisseria m eningitidis

Neisseria rneningifidis is an important pathogen because it causes life-threatening infections. The rapid course of meningococcal disease and the capacity of some serogroups to cause large-scale epidemics necessitates the use of sensitive, reliable and rapid typing methods to characterise strains. Molecular typing techniques for N. meningifidis are used for epidemiological purposes to investigate outbreaks and the spread of organisms and to examine the population genetic structure of the organism to understand better its variation and evolution. Many investigators have employed molecular typing methods and shown that meningococcal disease is associated with a variety of different epidemiological patterns. The choice of a typing method is dependent upon the epidemiological questions to be answered and on the population genetics of the organism under investigation. With highly clonal populations comprising independent non-recombining lineages such as serogroup A meningococci, ribotyping, multilocus enzyme electrophoresis (MLEE), pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST), PCR with arbitrary primers (RAPD) or with other gene-based primers each provides a constant measure of the relationship between strains. A mor