[Multilocus enzyme electrophoretic types of Neisseria meningitidis serogroup B and their epidemiologic significances].

In order to expand the epidemiologic relationships between the strains of Neisseria meningitidis serogroup B isolated from patients and carriers, 57 cases and 45 carrier isolates were collected in 11 provinces and 2 municipalities of China since the 1970s and their multilocus enzyme electrophoretic types and clonal population structures were studied by multilocus enzyme electrophoresis. It was primarily found that the above strains could be divided into 69 electrophoretic types (ET) and 13 clones. Among others, the clone I was the most important one, because the clone I represented 63.7% of all strains tested and 77.2% of the case isolates and its district distributions were quite wide since the 1970s. In addition, it was an obvious tendency that more and more of the case isolates gathered up the clone I since 1984 and the predominant ETs also occurred in the complex ET 1 and ET 24 of the clone I. As compared with the case isolates, the above carrier isolates displayed more heterogenetic types. Only 40% of all carrier isolates belonged to the above clone I and predominant ETs.