抗生素耐药性已成为对公共卫生的全球威胁,在受人为活动影响的环境中调查抗生素抗性细菌的存在引起了越来越多的兴趣。医院的污水处理厂是抗微生物细菌的重要储库,在建立有利环境的地方,促进抗性基因在不同菌种之间的增殖和转移。在我们的研究中,我们从墨西哥的5个医院污水场分离出243株菌株,属于21种不同的革兰氏阴性细菌。在46.9%(114/243)的分离物中检测到β-内酰胺酶的存在,属于肠杆菌科。我们共鉴定出169个β-内酰胺酶基因;blaTEM占33.1%,blaCTX-M占25.4%,blaKPC占25.4%,blaNDM8.8%,blaSHV为5.3%,和blaOXA-48的1.1%分布在12种不同的细菌中。在114个分离株中,发现50.8%含有至少一种碳青霉烯酶并排放到环境中。在六种柠檬酸杆菌属中发现了碳青霉烯酶blaKPC。和大肠杆菌,而在两个不同的肠杆菌属中检测到blaNDM。和大肠杆菌。值得注意的是,blaNDM-1在阴沟肠球菌的110KbIncFII接合质粒中被鉴定,E.xiangfangensis,和大肠杆菌在同一医院废水中。总之,医院废水显示存在携带高频率碳青霉烯酶blaKPC和blaNDM的肠杆菌科细菌。我们建议医院废水可作为细菌群落内耐药机制的储库,并为不同细菌菌株之间的耐药机制交换创造了最佳环境。
目的:本研究的意义在于其关于在墨西哥医院废水中鉴定出的抗生素抗性细菌和基因的流行和多样性的发现。该研究强调迫切需要加强监测和预防策略,以应对不断升级的抗生素耐药性挑战。通过肠杆菌科细菌中blaKPC和blaNDM等碳青霉烯酶基因的频率升高尤其明显。此外,这些抗性基因在共轭质粒上的鉴定突出了通过水平基因转移广泛传播的潜力。了解医院废水中抗生素耐药性的机制对于制定旨在减少传播的有针对性的干预措施至关重要。从而保护公众健康并保持抗微生物疗法的功效。
Antibiotic resistance has emerged as a global threat to public health, generating a growing interest in investigating the presence of antibiotic-resistant bacteria in environments influenced by anthropogenic activities. Wastewater treatment plants in hospital serve as significant reservoirs of antimicrobial-resistant bacteria, where a favorable environment is established, promoting the proliferation and transfer of resistance genes among different bacterial species. In our study, we isolated a total of 243 strains from 5 hospital wastewater sites in Mexico, belonging to 21 distinct Gram-negative bacterial species. The presence of β-lactamase was detected in 46.9% (114/243) of the isolates, which belonging to the Enterobacteriaceae family. We identified a total of 169 β-lactamase genes; blaTEM in 33.1%, blaCTX-M in 25.4%, blaKPC in 25.4%, blaNDM 8.8%, blaSHV in 5.3%, and blaOXA-48 in 1.1% distributed in 12 different bacteria species. Among the 114 of the isolates, 50.8% were found to harbor at least one carbapenemase and were discharged into the environment. The carbapenemase blaKPC was found in six Citrobacter spp. and E. coli, while blaNDM was detected in two distinct Enterobacter spp. and E. coli. Notably, blaNDM-1 was identified in a 110 Kb IncFII conjugative plasmid in E. cloacae, E. xiangfangensis, and E. coli within the same hospital wastewater. In conclusion, hospital wastewater showed the presence of Enterobacteriaceae carrying a high frequency of carbapenemase blaKPC and blaNDM. We propose that hospital wastewater serves as reservoirs for resistance mechanism within bacterial communities and creates an optimal environment for the exchange of this resistance mechanism among different bacterial strains.
OBJECTIVE: The significance of this study lies in its findings regarding the prevalence and diversity of antibiotic-resistant bacteria and genes identified in hospital wastewater in Mexico. The research underscores the urgent need for enhanced surveillance and prevention strategies to tackle the escalating challenge of antibiotic resistance, particularly evident through the elevated frequencies of carbapenemase genes such as blaKPC and blaNDM within the Enterobacteriaceae family. Moreover, the identification of these resistance genes on conjugative plasmids highlights the potential for widespread transmission via horizontal gene transfer. Understanding the mechanisms of antibiotic resistance in hospital wastewater is crucial for developing targeted interventions aimed at reducing transmission, thereby safeguarding public health and preserving the efficacy of antimicrobial therapies.