1例流行性脑脊髓膜炎病例的菌群鉴定及分析

Identification and analysis of a case of epidemic cerebrospinal meningitides

目的对2015年河南省1例流行性脑脊髓膜炎(流脑)病例的菌群进行分子分型鉴定及分析,为河南省流脑预防和控制工作提供科学依据。方法对患者脑脊液和血液标本以及37例密切接触者咽拭子标本进行细菌培养,提取DNA进行PCR及多位点序列分型(multilocus sequence typing,MLST)分析。用ELISA检测密切接触者血清标本的脑膜炎奈瑟菌A群和C群抗体水平。结果患者和1例密切接触者分离的菌株经细菌培养及PCR鉴定,分别为C群和B群脑膜炎奈瑟菌。MLST分型显示,患者和密切接触者标本分别为ST4821型和ST5664型,两者均为ST4821克隆群。37例密切接触者脑膜炎奈瑟菌A群和C群抗体阳性率分别为91.89%和21.62%,平均抗体质量浓度分别为6.50μg/m L和1.73μg/m L。结论引起流脑疫情的致病菌为C群ST4821型脑膜炎奈瑟菌,当地C群平均抗体含量偏低,需加强流脑A+C疫苗的接种,有效预防流脑的暴发。

Objective The genotype of flora from a case of epidemic cerebrospinal meningitis occurred in Henan Province was carried out in identification and analysis,on which a scientific basis will be provided in prevention and control of cerebrospinal meningitis. Methods The cerebrospinal fluid（CSF） and blood samples from the patient,and the throat swabs from 37 close contacts were tested by bacterial culture,polymerase chain reaction（PCR） and multilocus sequence typing（MLST）. The serum antibodies of serogroup A and C neisseria meningitides were detected by ELISA in the close contacts.Results The strains isolated from the patient and one case of close contacts belonged to serogroup C and B,and the MLST serotyping indicated that the neisseria meningitides detected in patient and the close contact belonged to ST4821 and ST5664 respectively,both attributed to ST4821 complex. The antibody positive rates of serogroup A and C neisseria meningitides were 91.89% and 21.62% respectively,and the average antibody levels were 6.50 μg/m L and 1.73 μg/m L in 37 close contacts. Conclusion An outbreak of epidemic cerebrospinal meningitides（ECM） was caused by serogroup C Neisseria meningitides belonging to lineage ST4821 complex. The local average antibody level of serogroup C neisseria meningitides was low,therefore,the vaccination against serogroup A and C neisseria meningitides should be strengthened in prevention same outbreak.