【摘要】 目的 探究珠海市健康人群咽部肺炎链球菌的携带情况及病原学特征。方法 随机采集珠海市552例健康受试者的咽拭子,联合应用细菌分离培养法与荧光定量PCR(qPCR)进行检测,对分离菌株采用基质辅助激光解吸电离飞行时间质谱(MALDI-TOFMS)进行鉴定,微量肉汤稀释法进行药敏试验,并利用全基因组测序进行多位点序列(MLST)分型、进化分析及毒力与耐药基因检测。结果 共分离到10株肺炎链球菌,药敏试验结果显示其对红霉素耐药率达100%,对四环素和头孢噻肟耐药率为80%,且70%为多重耐药。MLST分型分析鉴定出6种ST型,优势型为ST673;进化分析显示菌株分属4个分支。基因组分析证实所有菌株均携带关键毒力基因(lyt A、ply)及耐药基因erm(B)和tet(M)。结论 珠海市健康人群携带的肺炎链球菌呈现高耐药、高毒力特征,且存在克隆传播,亟需加强本地化监测与临床用药指导。更多还原

【Abstract】 Objective To analyze the carriage rate and etiological characteristics of pharyngeal Streptococcus pneumoniae in a healthy population in Zhuhai.Methods Throat swabs were randomly collected from 552healthy subjects in Zhuhai.The combined application of bacterial isolation and culture methods and fluorescence quantitative PCR(qPCR) was used for detection.The isolated bacterial strains were identified using matrix-assisted laser desorption ionization time-of-flight mass spectrometry(MALDI-TOF MS),and drug susceptibility tests were performed using the microbroth dilution method.Whole-genome sequencing was utilized for multi-locus sequence typing(MLST),evolutionary analysis,and detection of virulence and resistance genes.Results A total of 10 strains of Streptococcus pneumoniae were isolated.Antimicrobial susceptibility testing revealed a 100% resistance rate to erythromycin,80% resistance rate to tetracycline and cefotaxime,and 70% of the strains were multidrug-resistant.MLST typing analysis identified six sequence types(ST),with ST673 being the predominant type.Evolutionary analysis showed that the strains clustered into four distinct branches.Genomic analysis confirmed that all strains carried key virulence genes(lytA,ply) and resistance genes such as erm(B) and tet(M).Conclusion Streptococcus pneumoniae carried by healthy populations in Zhuhai exhibits high resistance rates,high virulence gene carriage,and evidence of clonal transmission.There is an urgent need to strengthen localized monitoring and guide clinical antibiotic use.更多还原