Wu Xuan, Zhang ZhiRong, Xiang Rong
Key Laboratory of Environmental Chemistry and Ecotoxicology of Organic Pollutants of Chongqing, Chongqing Ecological and Environment Monitoring Center, Chongqing, China.
Precision Medicine Center, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, Chongqing, China.
Microbiol Spectr. 2025 Jul;13(7):e0290024. doi: 10.1128/spectrum.02900-24. Epub 2025 Jun 9.
The increase in multidrug-resistant (MDR) Enterobacteriaceae presents a significant challenge to clinical treatment, particularly in infections where carbapenems and colistin serve as the last-resort antimicrobial agents. In this study, we isolated 119 non-repetitive gram-negative bacteria from MacConkey medium supplemented with imipenem and colistin. The isolates were dominated by (58.0%, = 69) and (31.1%, = 37). The predominant sequence types (STs) of were ST226, ST1286, and ST11738, whereas displayed ST152, ST395, and ST709 as major types. Genomic analysis identified in 44 strains and in 63 strains across various species. IncX3 ( = 57) and IncFII ( = 5) were the most common -carrying plasmid types. Several plasmid replicons were associated with genes, including IncI2, IncX4, and novel plasmids. Remarkably, we discovered four combinations of and mcr co-occurrence in 28 isolates, including /, /, / and /. Our findings reveal that chicken farms are significant reservoirs for both and genes, with frequent co-occurrence of these resistance determinants. The presence of these genes alongside other resistance factors, such as , highlights a critical public health risk. This study underscores the need for enhanced surveillance and intervention strategies to mitigate the spread of MDR pathogens from agricultural environments to clinical settings.IMPORTANCEThis study reveals that commercial poultry farms in China serve as critical reservoirs for MDR gram-negative bacteria harboring carbapenemase () and mobilized colistin resistance (mcr) genes. By analyzing 119 isolates, we uncovered extensive genetic diversity and plasmid-mediated co-occurrence of these resistance determinants, enabling bacteria to evade nearly all available treatments. Alarmingly, the horizontal transfer of resistance genes via highly mobile plasmids facilitates their spread across microbial communities and potentially into clinical settings. These findings underscore the urgent need to address antibiotic overuse in agriculture and strengthen surveillance under the One Health framework. The persistence of MDR pathogens in poultry environments highlights a significant risk for zoonotic transmission, emphasizing the necessity of coordinated interventions to curb the global antimicrobial resistance crisis.
多重耐药（MDR）肠杆菌科细菌的增加给临床治疗带来了重大挑战，尤其是在碳青霉烯类和黏菌素作为最后一线抗菌药物的感染中。在本研究中，我们从添加亚胺培南和黏菌素的麦康凯培养基中分离出119株非重复革兰氏阴性菌。分离菌株以（58.0%，n = 69）和（31.1%，n = 37）为主。的主要序列类型（STs）为ST226、ST1286和ST11738，而的主要类型为ST152、ST395和ST709。基因组分析在不同物种的44株菌株中鉴定出，在63株菌株中鉴定出。IncX3（n = 57）和IncFII（n = 5）是最常见的携带质粒类型。几种质粒复制子与基因相关，包括IncI2、IncX4和新型质粒。值得注意的是，我们在28株分离株中发现了四种与mcr共出现的组合，包括/、/、/和/。我们的研究结果表明，养鸡场是和基因的重要储存库，这些耐药决定因素经常同时出现。这些基因与其他耐药因子（如）一起存在，凸显了重大的公共卫生风险。本研究强调需要加强监测和干预策略，以减轻MDR病原体从农业环境向临床环境的传播。重要性本研究表明，中国的商业家禽养殖场是携带碳青霉烯酶（）和可移动黏菌素耐药性（mcr）基因的MDR革兰氏阴性菌的重要储存库。通过分析119株分离株，我们发现了这些耐药决定因素广泛的遗传多样性和质粒介导的共出现情况，使细菌能够逃避几乎所有可用治疗。令人担忧的是，耐药基因通过高度可移动的质粒进行水平转移，促进了它们在微生物群落中的传播，并可能传播到临床环境中。这些发现强调了迫切需要解决农业中抗生素的过度使用问题，并在“同一健康”框架下加强监测。MDR病原体在家禽环境中的持续存在凸显了人畜共患病传播的重大风险，强调了采取协调干预措施遏制全球抗菌药物耐药性危机的必要性。
