Table_3_Broiler Farms and Carcasses Are an Important Reservoir of Multi-Drug Resistant Escherichia coli in Ecuador.XLSX

Antimicrobial resistance (AMR) is a major health threat for public and animal health in the twenty-first century. In Ecuador, antibiotics have been used by the poultry industry for decades resulting in the presence of multi-drug resistant (MDR) bacteria in the poultry meat production chain, with the consequent risk for public health. This study evaluated the prevalence of ESBL/AmpC and mcr genes in third-generation cephalosporin-resistant Escherichia coli (3GC-R E. coli) isolated from broiler farms (animal component), broiler carcasses (food component), and human enteritis (human component) in Quito-Ecuador. Samples were collected weekly from November 2017 to November 2018. For the animal, food, and human components, 133, 335, and 302 samples were analyzed, respectively. Profiles of antimicrobial resistance were analyzed by an automated microdilution system. Resistance genes were studied by PCR and Sanger sequencing. From all samples, 122 (91.7%), 258 (77%), and 146 (48.3%) samples were positive for 3GC-R E. coli in the animal, food, and human components, respectively. Most of the isolates (472/526, 89.7%) presented MDR phenotypes. The ESBL blaCTX-M-55, blaCTX-M-3, blaCTX-M-15, blaCTX-M-65, blaCTX-M-27, and blaCTX-M-14 were the most prevalent ESBL genes while blaCMY-2 was the only AmpC detected gene. The mcr-1 gene was found in 20 (16.4%), 26 (10.1%), and 3 (2.1%) of isolates from animal, food, and human components, respectively. The implication of poultry products in the prevalence of ESBL/AmpC and mcr genes in 3GC-R must be considered in the surveillance of antimicrobial resistance.

抗菌素耐药性（Antimicrobial resistance, AMR）是21世纪公共卫生与动物卫生领域的重大健康威胁。在厄瓜多尔，家禽养殖业使用抗生素已有数十年历史，致使鸡肉生产链中出现多重耐药（multi-drug resistant, MDR）细菌，进而对公共健康造成潜在风险。本研究针对厄瓜多尔基多地区，检测了分离自肉鸡养殖场（动物源组分）、肉鸡胴体（食品源组分）及人类肠炎病例（人类源组分）的第三代头孢菌素耐药大肠埃希菌（3GC-R E. coli）中超广谱β-内酰胺酶（ESBL）/AmpC酶与mcr基因的携带率。研究于2017年11月至2018年11月期间每周采集样本，其中动物源、食品源及人类源组分的分析样本量分别为133份、335份及302份。本研究采用全自动微量稀释系统分析抗菌耐药谱，通过聚合酶链反应（PCR）与桑格测序检测耐药基因。所有样本中，动物源、食品源及人类源组分的第三代头孢菌素耐药大肠埃希菌阳性样本量分别为122份（占比91.7%）、258份（占比77%）及146份（占比48.3%）。多数分离株（472/526，占比89.7%）表现出多重耐药表型。最常见的超广谱β-内酰胺酶基因为blaCTX-M-55、blaCTX-M-3、blaCTX-M-15、blaCTX-M-65、blaCTX-M-27及blaCTX-M-14，而blaCMY-2是唯一检出的AmpC酶基因。在动物源、食品源及人类源分离株中，mcr-1基因的检出率分别为20株（占比16.4%）、26株（占比10.1%）及3株（占比2.1%）。在开展抗菌素耐药性监测工作时，需充分考虑家禽产品对第三代头孢菌素耐药大肠埃希菌中超广谱β-内酰胺酶、AmpC酶及mcr基因携带率的影响。