DataSheet_1_Emergence of Neonatal Sepsis Caused by MCR-9- and NDM-1-Co-Producing Enterobacter hormaechei in China.pdf

Mobile colistin resistance (mcr) genes represent an emerging threat to public health. Reports on the prevalence, antimicrobial profiles, and clonality of MCR-9-producing Enterobacter cloacae complex (ECC) isolates on a national scale in China are limited. We screened 3,373 samples from humans, animals, and the environment and identified eleven MCR-9-positive ECC isolates. We further investigated their susceptibility, epidemiology, plasmid profiles, genetic features, and virulence potential. Ten strains were isolated from severe bloodstream infection cases, especially three of them were recovered from neonatal sepsis. Enterobacter hormaechei was the most predominant species among the MCR-9-producing ECC population. Moreover, the co-existence of MCR-9, CTX-M, and SHV-12 encoding genes in MCR-9-positive isolates was globally observed. Notably, mcr-9 was mainly carried by IncHI2 plasmids, and we found a novel ~187 kb IncFII plasmid harboring mcr-9, with low similarity with known plasmids. In summary, our study presented genomic insights into genetic characteristics of MCR-9-producing ECC isolates retrieved from human, animal, and environment samples with one health perspective. This study is the first to reveal NDM-1- and MCR-9-co-producing ECC from neonatal sepsis in China. Our data highlights the risk for the hidden spread of the mcr-9 colistin resistance gene.

移动性粘菌素耐药（mcr）基因是一类对公共卫生构成新兴威胁的耐药基因。目前针对中国产MCR-9阴沟肠杆菌复合群（ECC）分离株的流行情况、抗菌谱及克隆性的全国性研究报道较为匮乏。本研究共筛查了来自人类、动物与环境的3373份样本，成功分离得到11株mcr-9阳性的ECC分离株，并对其药敏特性、流行病学特征、质粒图谱、遗传特征及毒力潜力开展了系统研究。其中10株分离自重症血流感染病例，其中3株更是来源于新生儿败血症患者。在产MCR-9的ECC群体中，霍氏肠杆菌（Enterobacter hormaechei）为最优势菌种。此外，本研究中的mcr-9阳性分离株普遍存在mcr-9、CTX-M与SHV-12耐药基因的共携带现象。尤为值得关注的是，mcr-9基因主要由IncHI2型质粒携带；本研究还发现了一种新型的约187kb的IncFII型质粒，其携带mcr-9基因，且与现有已知质粒的同源性较低。综上，本研究从同一健康（One Health）视角出发，对来源于人类、动物及环境样本的产MCR-9 ECC分离株的遗传特征开展了基因组层面的解析。本研究是国内首次报道从新生儿败血症病例中分离得到同时携带NDM-1与MCR-9的ECC分离株。本研究数据凸显了mcr-9粘菌素耐药基因存在隐匿传播的潜在风险。