Beta-Lactamase Producing Escherichia coli Isolates in Imported and Locally Produced Chicken Meat from Ghana

The use of antibiotics in food animals is of public health concern, because resistant zoonotic pathogens can be transmitted to humans. Furthermore, global trade with food may rapidly spread multi-resistant pathogens between countries and even continents. The purpose of the study was to investigate whether imported chicken meat and meat from locally reared chicken are potential sources for human exposure to multi resistant Escherichia coli isolates. 188 samples from imported and locally produced chicken meat were sampled and analyzed. 153 bacteria isolates were successfully cultured and identified as E. coli using MALDI-ToF. Of these 109 isolates were from meat whereas the remaining 44 were isolated from the cloaca of locally reared live chickens. Antimicrobial susceptibility test was done on the identified E. coli isolates. Additionally, beta-lactamases production (ESBL and/or AmpC) were phenotypically confirmed on all isolates showing resistance to cefpodoxime. Beta-lactamase producing (BLP) E. coli meat isolates were further genotyped. Antimicrobial resistance to four antibiotic markers with highest resistance was detected more frequently in isolates from local chickens compared to imported chickens (tetracycline 88.9% vs. 57.5%, sulphonamide 75.0% vs. 46.6%, ampicillin 69.4% vs. 61.6% and trimethoprim 66.7% vs. 38.4%). Beta-lactamase production was found in 29 E. coli meat isolates, with 56.9% of them being multiple drug resistant (≥ 3). The predominant phylogroup identified was B1 followed by A and D, with similar distribution among the isolates from meat of locally reared chickens and imported chickens. Beta-lactamase producing genotype blaCTX-M-15 (50%; 10/20) was the most frequently drug resistant gene detected. More BLP E. coli isolates were found in imported chicken meat compared to locally reared chickens, demonstrating that these isolates may be spreading through food trade. In conclusion, both imported and locally produced chicken meats are potential sources for human exposure to BLP E. coli.食用畜禽中抗生素的使用已成为公共卫生关注的重点问题，因为耐药性人畜共患病原体可传播至人类。此外，食品的全球贸易可能会在各国乃至各大洲之间快速传播多重耐药病原体。本研究旨在探究进口鸡肉与本地养殖鸡肉是否为人类接触多重耐药大肠埃希氏菌（Escherichia coli）分离株的潜在来源。研究采集并分析了188份进口及国产鸡肉样本，通过基质辅助激光解吸电离飞行时间质谱（MALDI-ToF）成功培养并鉴定出153株大肠埃希氏菌分离株，其中109株分离自鸡肉样本，剩余44株分离自本地养殖活鸡的泄殖腔。对上述鉴定出的大肠埃希氏菌分离株进行药敏试验。此外，对所有对头孢泊肟耐药的分离株进行表型验证，以确认其是否产β-内酰胺酶，包括超广谱β-内酰胺酶（ESBL）和/或AmpC型β-内酰胺酶。对产β-内酰胺酶（BLP）的鸡肉来源大肠埃希氏菌分离株进行进一步基因分型。与进口鸡肉来源的分离株相比，本地肉鸡来源的分离株对四种耐药率最高的抗生素标记物的耐药性检出率更高：四环素（88.9% vs 57.5%）、磺胺类（75.0% vs 46.6%）、氨苄西林（69.4% vs 61.6%）以及甲氧苄啶（66.7% vs 38.4%）。在29株鸡肉来源的产β-内酰胺酶大肠埃希氏菌分离株中，有56.9%为多重耐药菌（耐药≥3类抗生素）。鉴定出的优势系统群为B1群，其次为A群和D群，本地养殖鸡肉来源分离株与进口鸡肉来源分离株的系统群分布相似。产β-内酰胺酶基因型blaCTX-M-15（50%；10/20）是最常检出的耐药基因。进口鸡肉来源的产β-内酰胺酶大肠埃希氏菌分离株数量多于本地养殖肉鸡，提示此类分离株可能通过食品贸易进行传播。综上，进口鸡肉与国产鸡肉均为人类接触产β-内酰胺酶大肠埃希氏菌的潜在来源。