中国C群脑膜炎奈瑟菌脉冲场凝胶电泳分析

目的对中国C群脑膜炎奈瑟菌分离株进行脉冲场凝胶电泳（PFGE）分析，了解安徽省C群流行性脑脊髓膜炎（流脑）暴发菌株及国内C群脑膜炎奈瑟菌菌株的分子流行病学特征。方法212株C群脑膜炎奈瑟菌菌株分离自流脑患者、密切接触者和健康人群鼻咽部，包括安徽省C群流脑菌株48株，其中38株与C群流脑暴发相关。脉冲场凝胶电泳选用NheI限制性内切酶，聚类分析选用BioNumerics软件。结果212株C群脑膜炎奈瑟菌菌株共分为43个PFGE带型，命名为AH1～AH43，AH1是中国C群脑膜炎奈瑟菌主要的带型，占69．3％（”=147），分布于11个省市。安徽省48株C群菌株共分为3个PFGE型别（AH1、AH2、AH3），45株（93．8％）为AH1型。安徽省38株与C群流脑暴发相关的菌株中，37株（97．4％）为AH1型。全国53株流脑患者分离菌株中，AH1型菌株占67．9％（36／53）；121株流脑病例密切接触者分离菌株中，AH1型占71．9％（87／121），38株健康人群鼻咽部分离菌株中，AH1型占63．2％（24／38）。结论AH1型C群脑膜炎奈瑟菌是中国目前C群流脑流行的主要克隆群，安徽省C群流脑暴发是由AH1型C群脑膜炎奈瑟菌引起的，已在全国呈扩散流行的趋势。

Molecular typing of Neisseria meningitidis serogroup C strains with pulsed field gel electrophoresis in China

OBJECTIVE: To study the characteristics of epidemiology and molecular typing on Neisseria meningitidis serogroup C strains associated with outbreaks of Anhui province and sporadic cases in China, using pulsed field gel electrophoresis (PFGE). METHODS: 212 Neisseria meningitidis serogroup C strains were isolated from invasive meningococcal cases, close contacts and healthy carriers, including 48 strains from Anhui province with 38 strains associated with serogroup C outbreaks. PFGE were performed by genomic DNA digestion with Nhe I restriction enzyme. The results of PFGE were analyzed by BioNumerics software (Version 4.0, Applied Maths BVBA, Belgium). RESULTS: A total number of 212 Neisseria meningitidis serogroup C isolates were typed by 43 patterns, named AH1 to AH43. In China, AH1 pattern was the major PFGE pattern with 69.3% (n = 147) of all strains, distributed in 11 provinces. Three types of PFGE patterns (AH1 to AH3) were found in 48 strains from Anhui province, in which, 93.8% (n = 45) belonged to AH1. 97.4% (n = 37) of 38 strains associated with serogroup C outbreaks in Anhui province showed AH1 pattern. A total of 53 serogroup C strains were isolated from invasive meningococcal cases with 67.9% (36/53) of AH pattern. 71.9% (87/121) of serogroup C strains isolated from contacts of invasive meningococcal cases was AH1 pattern and 63.2% (24/38) of the strains from healthy carriers showed AH1 pattern. CONCLUSION: By PFGE typing and analysis, AH1 pattern of Neisseria meningitidis serogroup C strains was proved to be the main clone which causing the outbreaks in Anhui province and might be responsible for the sporadic serogroup C meningococcal disease epidemics else where in the country.