Instituto Nacional de Salud Pública (INSP), Centro de Investigación Sobre Enfermedades Infecciosas (CISEI), Cuernavaca, Morelos, Mexico.
Facultad de Medicina, Hospital Universitario "Dr. José Eleuterio González", Departamento de Enfermedades Infecciosas, Universidad Autónoma de Nuevo León, Monterrey, Mexico.
Appl Environ Microbiol. 2024 Aug 21;90(8):e0116524. doi: 10.1128/aem.01165-24. Epub 2024 Jul 16.
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 family. We identified a total of 169 β-lactamase genes; in 33.1%, in 25.4%, in 25.4%, 8.8%, in 5.3%, and 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 was found in six spp. and , while was detected in two distinct spp. and . Notably, was identified in a 110 Kb IncFII conjugative plasmid in , and within the same hospital wastewater. In conclusion, hospital wastewater showed the presence of carrying a high frequency of carbapenemase and . 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.
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 and within the 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.
抗生素耐药性已成为全球公共卫生的一大威胁，促使人们越来越关注研究受人为活动影响的环境中存在的抗生素耐药细菌。医院污水处理厂是抗菌耐药细菌的重要储存库，在那里建立了有利的环境，促进了不同细菌物种之间耐药基因的增殖和转移。在我们的研究中，我们从墨西哥的 5 个医院废水场共分离出 243 株，属于 21 种不同的革兰氏阴性细菌。在 243 株分离株中，有 46.9%（114/243）检测到β-内酰胺酶，属于 家族。我们共鉴定出 169 种β-内酰胺酶基因；33.1%为 ，25.4%为 ，25.4%为 ，8.8%为 ，5.3%为 ，1.1%为 ，分布在 12 种不同的细菌中。在 114 株分离株中，有 50.8%至少携带一种碳青霉烯酶并被排放到环境中。在 6 种 spp.和 中发现了碳青霉烯酶 ，在 2 种不同的 spp.和 中发现了 。值得注意的是，在 中， 被鉴定为一个 110 Kb 的 IncFII 可接合质粒，在同一医院废水中 和 中也发现了 。总之，医院废水显示出携带高频率碳青霉烯酶 和 的 存在。我们提出，医院废水是细菌群落中耐药机制的储存库，并为不同细菌菌株之间耐药机制的交换创造了最佳环境。
本研究的重要性在于它在墨西哥医院废水检测到的抗生素耐药细菌和基因的流行率和多样性方面的发现。研究强调了加强监测和预防策略的必要性，以应对日益严重的抗生素耐药性挑战，特别是在 家族中发现的 和 等碳青霉烯酶基因的高频率。此外，这些耐药基因在可接合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的机制对于开发靶向干预措施以减少传播至关重要，从而保护公共健康并维持抗菌治疗的疗效。
