Molecular characterizations of serogroup B Neisseria meningitidis strains circulating in Beijing

Neisseria meningitidis (N. Meningitidis) is classified into 13 serogroups based on the immunological reactivity of the capsular polysaccharide.1 Serogourps A,B and C are responsible for over 90% of meningococcal disease.2In developed countries, endemic disease is generally caused by serogroups B and C. Epidemics due to serogroup B have also occurred in Brazil, Chile, Cuba,Norway and, more recently, in New Zealand.2 In China,serogroup A is the most common cause of epidemics. In recent years, the number of meningococcal meningitis cases in China attributed to serogroups B and C has substantially increased.3,4