Department of Veterinary and Pest Control Services, Federal Ministry of Agriculture and Rural Development, Abuja, Nigeria.
Nigeria Field Epidemiology and Laboratory Training Programme, Abuja, Nigeria.
Antimicrob Resist Infect Control. 2021 Mar 23;10(1):58. doi: 10.1186/s13756-021-00930-x.
Inappropriate use of antimicrobial agents in animal production has led to the development of antimicrobial resistance (AMR) in foodborne pathogens. Transmission of AMR foodborne pathogens from reservoirs, particularly chickens to the human population does occur. Recently, we reported that occupational exposure was a risk factor for multidrug-resistant (MDR) Escherichia coli (E. coli) among poultry-workers. Here we determined the prevalence and genetic relatedness among MDR E. coli isolated from poultry-workers, chickens, and poultry environments in Abuja, Nigeria. This study was conducted to address the gaps identified by the Nigerian AMR situation analysis.
We conducted a cross-sectional study among poultry-workers, chickens, and poultry farm/live bird market (LBM) environments. The isolates were tested phenotypically for their antimicrobial susceptibility profiles, genotypically characterized using whole-genome sequencing (WGS) and in silico multilocus sequence types (MLST). We conducted a phylogenetic single nucleotide polymorphism (SNPs) analysis to determine relatedness and clonality among the isolates.
A total of 115 (26.8%) out of 429 samples were positive for E. coli. Of these, 110 isolates were viable for phenotypic and genotypic characterization. The selection comprised 47 (42.7%) isolates from poultry-workers, 36 (32.7%) from chickens, and 27 (24.5%) from poultry-farm or LBM environments. Overall, 101 (91.8%) of the isolates were MDR conferring resistance to at least three drug classes. High frequency of resistance was observed for tetracycline (n = 102; 92.7%), trimethoprim/sulfamethoxazole (n = 93; 84.5%), streptomycin (n = 87; 79.1%) and ampicillin (n = 88; 80%). Two plasmid-mediated colistin genes-mcr-1.1 harboured on IncX4 plasmids were detected in environmental isolates. The most prevalent sequence types (ST) were ST-155 (n = 8), ST-48 (n = 8) and ST-10 (n = 6). Two isolates of human and environmental sources with a SNPs difference of 6161 originating from the same farm shared a novel ST. The isolates had similar AMR genes and plasmid replicons.
MDR E.coli isolates were prevalent amongst poultry-workers, poultry, and the poultry farm/LBM environment. The emergence of MDR E. coli with novel ST in two isolates may be plasmid-mediated. Competent authorities should enforce AMR regulations to ensure prudent use of antimicrobials to limit the risk of transmission along the food chain.
动物生产中抗菌药物的不适当使用导致了食源性病原体的抗菌药物耐药性（AMR）的发展。食源性病原体从储存库，特别是鸡传播给人类的情况确实存在。最近，我们报告职业接触是家禽工人中多药耐药（MDR）大肠杆菌（E. coli）的危险因素。在这里，我们确定了在尼日利亚阿布贾从家禽工人、鸡和家禽环境中分离出的 MDR 大肠杆菌的流行率和遗传相关性。这项研究是为了解决尼日利亚抗菌药物耐药性情况分析中确定的差距。
我们在家禽工人、鸡和家禽养殖场/活禽市场（LBM）环境中进行了横断面研究。使用表型方法测试分离株的抗菌药物敏感性谱，使用全基因组测序（WGS）和计算机多基因序列类型（MLST）进行基因特征分析。我们进行了单核苷酸多态性（SNP）分析的系统发育分析，以确定分离株之间的亲缘关系和克隆性。
在 429 个样本中，共有 115 个（26.8%）为大肠杆菌阳性。其中，110 个分离株可用于表型和基因特征分析。选择包括来自家禽工人的 47 个（42.7%）分离株、来自鸡的 36 个（32.7%）和来自家禽养殖场或 LBM 环境的 27 个（24.5%）。总体而言，101 个（91.8%）分离株为 MDR，对至少三种药物类别具有耐药性。耐四环素（n=102；92.7%）、磺胺甲恶唑/甲氧苄啶（n=93；84.5%）、链霉素（n=87；79.1%）和氨苄西林（n=88；80%）的耐药率很高。两种质粒介导的黏菌素基因-mcr-1.1 位于 IncX4 质粒上，在环境分离株中检测到。最常见的序列类型（ST）是 ST-155（n=8）、ST-48（n=8）和 ST-10（n=6）。来自同一农场的两株人源和环境源分离株，SNP 差异为 6161，具有新的 ST。分离株具有相似的 AMR 基因和质粒复制子。
MDR 大肠杆菌分离株在家禽工人、家禽和家禽养殖场/LBM 环境中普遍存在。两株来自人和环境来源、SNP 差异为 6161 的 MDR E. coli 具有新的 ST，可能是质粒介导的。主管部门应执行抗菌药物耐药性法规，确保合理使用抗菌药物，以限制沿食物链传播的风险。
