摘要
      粘菌素耐药性的出现被认为是对公众健康的威胁，最近在动物、环境和人类来源中报道了粘菌素耐药细菌。然而，尚未对鸭场中粘菌素抗性细菌的流行和传播进行调查，尤其是鸭场周围的环境污染。我们调查了中国沿海养鸭场mcr-1阳性大肠杆菌的流行情况和分子特征。从鸭场和周围环境的1112个样本中采集了360个mcr-1阳性大肠杆菌分离株。广东省mcr-1阳性大肠杆菌的患病率高于我们检测的其他两个省份。PFGE分析表明，mcr-1阳性大肠杆菌在养鸭场和周围环境（包括水和土壤）之间的克隆传播。MLST分析表明，ST10比ST1011、ST117和ST48更常见。系统发育基因组分析还表明，从不同城市收集的mcr-1阳性大肠杆菌被分配到同一谱系，并且mcr-1主要位于IncI2和IncHI2质粒上。基因组环境分析表明，可移动基因元件ISApl1很可能在mcr-1的水平传播中发挥关键作用。WGS进一步揭示了mcr-1与27种不同的ARG相关。我们的研究结果强调，迫切需要对人类、动物和环境进行有效的粘菌素耐药性监测。
Abstract
The emergence of colistin-resistance is considered a threat to public health and colistin-resistant bacteria have recently been reported in animal, environmental and human sources. Whereas, the epidemic and dissemination of colistin-resistant bacteria in duck farms have not been surveyed, especially the surrounding environmental contamination from duck farms. We investigated the prevalence and molecular characteristics of mcr-1-positive E. coli from duck farms in coastal China. 360 mcr-1-positive E. coli isolates were collected from 1112 samples from duck farms and surrounding environments. The prevalence of mcr-1-positive E. coli in Guangdong province was higher than other two provinces we examined. PFGE analysis indicated clonal spread of mcr-1-positive E. coli between duck farms and surrounding environments, including water and soil. MLST analysis demonstrated that ST10 was more common than ST1011, ST117, and ST48. Phylogenomic analysis also suggested mcr-1-positive E. coli collected from distinct cities were assigned to the same lineage and mcr-1 was primarily located on IncI2 and IncHI2 plasmids. Genomic environment analysis showed mobile gene elements ISApl1 most likely plays a key role in the horizontal transmission of mcr-1. WGS further revealed that mcr-1 was found associated with 27 different ARGs. Our findings emphasize the urgent need for effective colistin resistance surveillance in humans, animals and the environment.

https://www.sciencedirect.com/science/article/abs/pii/S0944501323000502