Abstract：
Antimicrobial-resistant (AMR) pathogens are a significant threat to public health worldwide. However, the primary carrier of AMR genes, particularly against last-resort antibiotics, is still only partially studied in Chinese hospitals. In a sentinel hospital in China, we collected 157 E. coli strains from patients between January and July 2021. One blaNDM-1-, nine blaNDM-5-, and one mcr-1-positive E. coli recovered from inpatients were identified as resistant to meropenem and colistin. There are 37 virulence genes discovered in the 11 strains, including astA in strain EC21Z-147 (O128: H4), which belongs to the enteroaggregative E. coli (EAEC). The blaNDM gene is distributed into distinct ST types, including ST48, ST616, ST410, ST711, and ST2003, while the mcr-1 gene was identified in ST117. The conjugative plasmids IncX3, IncI1-I, and IncI2 mediated the blaNDM-5 and mcr-1 genes detected among inpatients. Notably, the youngest age at which mcr-1-positive E. coli has been reported was at one day old, in a child in which the strain is closely related to strains with animal origins. Hospitals are major environments for the spread and dissemination of critical virulence and AMR genes, which requires active monitoring systems at the genome level to surveil the spread of virulence and AMR.
摘要：
抗菌素耐药性(AMR)病原体是全球公共卫生的重大威胁。然而,AMR基因的主要载体，特别是针对最后的抗生素，仍然只在中国医院进行了部分研究。在中国的哨兵医院，我们从2021年1月至7月的患者中收集了157株大肠杆菌。一个blaNDM-1-，九blaNDM-5-，从住院患者中回收的一株mcr-1阳性大肠杆菌被鉴定为对美罗培南和粘菌素具有抗性。在11个菌株中发现了37个毒力基因，包括菌株EC21Z-147（O128：H4）中的astA，属于肠聚集性大肠杆菌(EAEC)。blaNDM基因分布在不同的ST类型中，包括ST48，ST616，ST410，ST711和ST2003，而在ST117中鉴定了mcr-1基因。共轭质粒IncX3，IncI1-I，IncI2介导在住院患者中检测到的blaNDM-5和mcr-1基因。值得注意的是,据报道，mcr-1阳性大肠杆菌的最小年龄是一天大，在一个孩子中，该菌株与动物起源的菌株密切相关。医院是传播和传播关键毒力和AMR基因的主要环境，这需要基因组水平的主动监测系统来监测毒力和AMR的传播。
