广东省2007-2016年人源沙门菌流行现状及病原学特征

Circulation and etiological characterization of Salmonella enterica serotype in human in Guangdong province, 2007-2016

目的 了解广东省人源沙门菌1，4，[5]，12：i：-的流行现状、耐药性与分子特征。方法 对2007－2016年广东省沙门菌腹泻病例监测检出的人源沙门菌1，4，[5]，12：i：-进行药物敏感试验、PCR检测和PFGE分型。结果 2007－2016年广东省共检出人源沙门菌1，4，[5]，12：i：-2 960株，检出率逐年增多，至2015年成为广东省人源沙门菌中最主要的血清型。病例中男女性别比为1.58∶1，发病年龄以婴幼儿为主。沙门菌1，4，[5]，12：i：-除对亚胺培南100%敏感外，对其他17种抗生素均有不同程度的耐药。2011－2016年对头孢他啶、头孢噻肟和环丙沙星的耐药率呈上升趋势。多重耐药现象严重，具有ASSuT多重耐药的有70.62%（435/616），具有ACSuGSTTm多重耐药的有27.11%（167/616）。第Ⅱ相鞭毛蛋白不表达主要（75.53%）是缺失fljA、fljB和hin基因，但保留了iroB、STM2740、STM2757基因，共有8种不同的缺失方式。2 347株菌有934种PFGE谱型别，表现出较大的指纹图谱多态性，最主要的优势PFGE谱型为JPXX01.GD0226型（97株菌，4.13%）。168株沙门菌1，4，[5]，12：i：-的PFGE图谱与鼠伤寒沙门菌PFGE图谱一致。结论 沙门菌1，4，[5]，12：i：-已成为广东省人源沙门菌中最主要的血清型，且多重耐药现象严重，第Ⅱ相鞭毛蛋白不表达主要由缺失fljA、fljB和hin基因引起，其PFGE型别多样，呈遗传多态性。

Objective To understand the circulation, drug resistance and molecular characteristics of Salmonella 1,4,[5],12：i：-in human in Guangdong province. Methods Salmonella 1,4,[5],12：i：-isolated from diarrhea patients in Guangdong during 2007-2016 were detected for drug resistance, genes and PFGE characteristics. Results A total of 2 960 strains Salmonella 1,4,[5],12：i：-were isolated from human diarrhea cases during this period. The positive rates of the isolation increased year by year. The male to female ratio of the infection cases was 1.58：1, and the infection mainly occurred in infants and young children. Except imipenem, Salmonella 1,4,[5],12：i：-was resistant to other 17 antibiotics to some extent. The drug resistant rates to ceftazidime, cefotaxime and ciprofloxacin increased from 2011 to 2016. Multi-drug resistance was serious, for example, the multi-drug resistant strains with ASSuT accounted for 70.62% （435/616） and the multi-drug resistant strains with ACSuGSTTm accounted for 27.11% （167/616）. The lack of fljA, fljB and hin genes, as well as the retaining of iroB, STM2740, STM2757 genes, resulted in the unable expression of FljBenx gene with 8 different defection profiles. There were 934 different PFGE patterns observed in 2 347 strains, which displayed a relatively large fingerprint polymorphism. The major PFGE pattern was JPXX01. GD0226, which was found in 97 strains, accounting for 4.13% （97/2 347）. The PFGE patterns in 168 Salmonella 1,4,[5],12：i：-strains were consistent with that of Salmonella typhimurium. Conclusions Salmonella 1,4,[5], 12：i：-strains has become the major serotype of Salmonella that cause diarrhea in human in Guangdong. The multi-drug resistance of Salmonella 1,4,[5], 12：i：-was serious, and since the defection of fljA, fljB and hin genes, the expression of FljBenx protein failed. The PFGE results were diverse, which displayed polymorphism in inheritance.