Objective: To understand the circulation, drug resistance and molecular characteristics of Salmonella1, 4, [5], 12: i:- in human in Guangdong province. Methods:Salmonella1, 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 Salmonella1, 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, Salmonella1, 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 Salmonella1, 4, [5], 12: i: - strains were consistent with that of Salmonella typhimurium. Conclusions:Salmonella1,4,[5], 12: i: - strains has become the major serotype of Salmonella that cause diarrhea in human in Guangdong. The multi-drug resistance of Salmonella1,4, [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.
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。.