1970—2019年四川省黄疸出血群钩端螺旋体基因分型特征

Genotyping of leptospira interrogans serogroup icterohaemorrhagiae in Sichuan Province from 1970 to 2019

目的了解四川省黄疸出血群钩端螺旋体基因分型特征,为钩体病分子流行病学调查和防治工作提供科学依据。方法采用多位点序列分型方法(Multilocus sequence typing,MLST)对四川省1970—2019年间从病人和宿主动物体内分离到的102株黄疸出血群钩体菌株进行基因分型,使用BioNumerics Version 7.6软件对MLST分型结果进行聚类分析。结果102株钩体菌分为5个ST型别,遗传相似度为20%~100%,型别为ST1、ST17、ST36、ST98、ST203,其中ST1为优势基因型,其次为ST17。通过BN软件聚类表明,102株钩体菌隶属于4个克隆群,1970—1981年间分离的22株黄疸出血群钩体包含以上5个ST型,呈多样化,1982年后分离的菌株仅含ST1和ST17型。ST1型分布范围最广泛,宿主动物类型最多。结论四川省黄疸出血群钩体菌株具备较高的遗传多样性,有潜在的感染人的风险,应加强对钩体主要宿主动物的监测工作。

Objective This study aimed to analyze the genotyping of Leptospira interrogans serogroup Icterohaemorrhagiae isolated in Sichuan Province,and to provide scientific basis for molecular epidemiological investigation and prevention of leptospirosis.Methods Multilocus sequence typing(MLST)was used to study the genotyping of 102 isolates of Leptospira interrogans serogroup Icterohaemorrhagiae isolated from patients and host animals in Sichuan province from 1970 to 2019.Bio Numerics Version 7.6 software was used for clustering analysis of MLST typing results.Results The 102 Leptospira interrogans isolates were divided into 5 ST types,including ST1,ST17,ST36,ST98 and ST203,among which ST1 was the dominant genotype,then followed by ST17.The results showed that 102 strains of Leptospira interrogans belonged to four clones by BN software clustering.The 22 strains of Leptospira interrogans isolated from 1970 to 1981 contained the above 5 ST types and were diverse,while the strains isolated after 1982 only contained ST1 and ST17.The ST1 type had the most extensive distribution and the most host animal types.Conclusions The Leptospira interrogans serogroup Icterohaemorrhagiae strains in Sichuan province have high genetic diversity and have potential risk of human infection.Therefore,the monitoring of the main host animals of Leptospira interrogans should be strengthened.