Distribution of serogroups and sequence types in disease-associated and carrier strains ofNeisseria meningitidisisolated in China between 2003 and 2008

Abstract

SUMMARYGiven the unpredictability ofNeisseria meningitidisoutbreaks and the increased prevalence of serogroup C strains following the introduction of serogroup A-based vaccines, we conducted an analysis of serogroups and sequence types (STs) in disease-associated and carrierN. meningitidisisolates that have emerged in China since 2003. We used multilocus sequence-typing techniques to investigate 371N. meningitidisstrains isolated from patients with meningitis and healthy carriers. Two lineages were identified in serogroup A and C isolates, genotyped as the ST5 complex and ST4821 complex, respectively. Both clonal complexes were found throughout China, although ST4821 was more concentrated in the eastern region of the country. The ST5 complex has been persistent in China since the late 1980s and has since spread across the entire country. Isolates belonging to the ST4821 complex have been a dominant lineage since 2003.