2006-2016年四川省猪链球菌血清2型多位点序列分型分析

Multi locus sequence typing of Streptococcus suis serotype 2 isolated in Sichuan province,2006-2016

目的了解四川省2006-2016年猪链球菌血清2型菌株的分子流行病学特征,分析10年间分离株之间的关联,为四川省人感染猪链球菌病防控提供参考依据。方法通过聚合酶链反应法扩增猪链球菌基因组上的7个管家基因片段并进行测序,对2006-2016年四川省猪链球菌病例样本中分离的27株猪链球菌血清2型菌株进行多位点序列分型分析。结果 27株猪链球菌血清2型菌株分为2个ST型,其中19株为ST7型,其余为ST1型;2006-2007年以ST7型为主,2007年后主要为ST1型。结论近年四川省人感染猪链球菌病均为散发,未出现暴发疫情,可能与流行菌株的ST型变化相关。

Objective To understand the molecular epidemiological characteristics of Streptococcus suis （S. suis） serotype 2 isolated in Sichuan province from 2006 to 2016 and provide evidence for the prevention and control of human infection with S. suis. Methods Through the polymerase chain reaction （PCR） amplification of the fragments of 7 housekeeping genes and sequencing, multi locus sequence typing （MLST） of 27 strains of S. suis serotype 2 isolated from clinical patients in Sichuan from 2006 to 2016 was conducted. Results MLST typing results showed that the 27 strains could be classified into 2 sequence types, i.e. ST1 and ST7. 19 strains belonged to ST7 and 8 strains belonged to ST1. From 2006 to 2007, the predominant ST was ST7. After 2007, the predominant ST was ST1. Conclusion Sporadic human infection with S. suis occurred in Sichuan in recent years without outbreaks, which might be associated with the change of the ST of the pathogen.