Unit for Environmental Sciences and Management, North-West University, Potchefstroom, 2531, South Africa; Gastrointestinal Research Unit, Department of Surgery, School of Clinical Medicine, University of the Free State, Bloemfontein 9300, South Africa.
Unit for Environmental Sciences and Management, North-West University, Potchefstroom, 2531, South Africa.
Food Microbiol. 2024 Jun;120:104476. doi: 10.1016/j.fm.2024.104476. Epub 2024 Jan 10.
Globally, the spread of multidrug-resistant Pseudomonas aeruginosa, Escherichia coli, and Klebsiella pneumoniae from food to humans poses a severe threat to public health. The aim of this study was to assess the co-occurrence of colistin and β-lactamase resistance genes in E. coli, K. pneumoniae, and P. aeruginosa strains isolated from faeces of abattoir broiler chickens. The E. coli, P. aeruginosa and K. pneumoniae isolates were successfully detected from faecal samples by polymerase chain reaction (PCR) at infection rates of 60.7%, 22.5% and 16.7% respectively. The isolates displayed the highest levels of antibiotic resistance (AR) against ampicillin (82.3%) and amoxicillin-clavulanic acid (74.2%) for E. coli, followed by cefoxitin (70.6%) for K. pneumoniae, whilst P. aeruginosa displayed 26.1% antibiotic resistance (AR) against both ampicillin and colistin sulphate. The colistin mcr-1 gene was harboured by 46.8%, 47.1% and 21.7%, E. coli, K. pneumonia and P. aeruginosa isolates respectively. Ten out of 62 (16.1%), 6/17 (35.3%), 4/23 (17.4%) isolates were phenotypically classified as ESBL E. coli, K. pneumoniae, and P. aeruginosa respectively. The ESBL-E. coli isolates respectively possessed bla (60%), bla (20%) and bla (10%) genes. The ESBL-K. pneumoniae harboured, bla (50%), bla (33%), bla (17%), and bla (17%) genes respectively, whilst, P. aeruginosa isolates respectively carried bla (75%), bla (50%), bla (25%) and bla (25%) genes. Molecular analysis identified the blaβ-lactamase-encoding genes collectively from E. coli, P. aeruginosa, K. pneumoniae isolates. Colistin and β-lactamase genes were present in only 16.7%, 6.9%, and 2.9% of E. coli, K. pneumoniae, and P. aeruginosa isolates, respectively. A total of 17, 7 and 3 isolates for E. coli, K. pneumoniae and P. aeruginosa respectively carried both colistin and β-lactamase antibiotics resistant genes. This is a public health threat that points to a challenge in the treatment of infections caused by these zoonotic bacteria. Data generated from this study will contribute to formulation of new strategies for combating spread of E. coli, K. pneumoniae, and P. aeruginosa isolates as well as prevention of their AR development.
从全球范围来看，食源性病原体多重耐药铜绿假单胞菌、大肠埃希氏菌和肺炎克雷伯菌向人类的传播对公共卫生构成了严重威胁。本研究旨在评估从屠宰场肉鸡粪便中分离的大肠埃希氏菌、肺炎克雷伯菌和铜绿假单胞菌菌株中同时存在黏菌素和β-内酰胺酶耐药基因的情况。通过聚合酶链反应（PCR）从粪便样本中成功检测到大肠埃希氏菌、铜绿假单胞菌和肺炎克雷伯菌，感染率分别为 60.7%、22.5%和 16.7%。分离株对氨苄西林（82.3%）和阿莫西林克拉维酸（74.2%）的抗生素耐药性（AR）最高，其次是头孢西丁（70.6%），而铜绿假单胞菌对氨苄西林和黏菌素硫酸盐的抗生素耐药性（AR）分别为 26.1%。mcr-1 黏菌素基因分别存在于 46.8%、47.1%和 21.7%的大肠埃希氏菌、肺炎克雷伯菌和铜绿假单胞菌分离株中。62 株大肠埃希氏菌中有 10 株（16.1%）、17 株肺炎克雷伯菌中有 6 株（35.3%）、23 株铜绿假单胞菌中有 4 株（17.4%）为表型 ESBL 大肠埃希氏菌、肺炎克雷伯菌和铜绿假单胞菌。ESBL-大肠埃希氏菌分离株分别携带 bla（60%）、bla（20%）和 bla（10%）基因。ESBL-肺炎克雷伯菌分别携带 bla（50%）、bla（33%）、bla（17%）和 bla（17%）基因，而铜绿假单胞菌分别携带 bla（75%）、bla（50%）、bla（25%）和 bla（25%）基因。分子分析从大肠埃希氏菌、铜绿假单胞菌和肺炎克雷伯菌分离株中共鉴定出 blaβ-内酰胺酶编码基因。仅在 16.7%、6.9%和 2.9%的大肠埃希氏菌、肺炎克雷伯菌和铜绿假单胞菌分离株中发现了黏菌素和β-内酰胺酶抗生素耐药基因。大肠埃希氏菌、肺炎克雷伯菌和铜绿假单胞菌分别有 17、7 和 3 株携带黏菌素和β-内酰胺酶抗生素耐药基因。这是对公共卫生的威胁，表明这些人畜共患病原体引起的感染治疗面临挑战。本研究产生的数据将有助于制定新的策略，以对抗大肠埃希氏菌、肺炎克雷伯菌和铜绿假单胞菌分离株的传播，并防止其抗生素耐药性的发展。
