University of Geneva, Faculty of Sciences, Earth and Environmental Sciences, Institute F. A. Forel and Institute of Environmental Sciences, Bd Carl-Vogt 66, CH-1211, Geneva 4, Switzerland; King Abdulaziz City for Science and Technology, Joint Centers of Excellence Program, Prince Turki the 1st St, Riyadh, 11442, Saudi Arabia.
School of Public Health, Faculty of Medicine, University of Kinshasa, B.P. 11850, Kinshasa XI, Congo.
Ecotoxicol Environ Saf. 2020 Sep 1;200:110767. doi: 10.1016/j.ecoenv.2020.110767. Epub 2020 May 26.
The occurrence and dissemination of antibiotic resistant genes (ARGs) that are associated with clinical pathogens and the evaluation of associated risks are still under-investigated in developing countries under tropical conditions. In this context, cultivable and molecular approaches were performed to assess the dissemination of bacteria and the antibiotic resistance genes in aquatic environment in Kinshasa, Democratic Republic of the Congo. Cultivable approach quantified β-lactam, carbapenem resistant, and total Escherichia coli and Enterobacteriaceae in river sediments and surface waters that receive raw hospital effluents. The molecular approach utilized Quantitative Polymerase Chain Reaction (qPCR) to quantify the total bacteria and the richness of relevant bacteria (Escherichia coli, Enterococcus, and Pseudomonas), and antibiotic resistance genes (ARGs: bla, bla, bla, bla) in sediment samples. Statistical analysis were employed to highlight the significance of hospital contribution and seasonal variation of bacteria and ARGs into aquatic ecosystems in suburban municipalities of Kinshasa, Democratic Republic of the Congo. The contribution of hospitals to antibiotic resistance proliferation is higher in the dry season than during the wet season (p < 0.05). Hospital similarly contributed Escherichia coli, Enterococcus, and Pseudomonas and ARGs significantly to the sediments in both seasons (p < 0.05). The organic matter content correlated positively with E. coli (r = 0.50, p < 0.05). The total bacterial load correlated with Enterococcus, and Pseudomonas (0.49 < r < 0.69, p < 0.05). Each ARG correlated with the total bacterial load or at least one relevant bacteria (0.41 < r < 0.81, p < 0.05). Our findings confirm that hospital wastewaters contributed significantly to antibiotic resistance profile and the significance of this contribution increased in the dry season. Moreover, our analysis highlights this risk from untreated hospital wastewaters in developing countries, which presents a great threat to public health.
在热带条件下的发展中国家，与临床病原体相关的抗生素耐药基因 (ARGs) 的发生和传播及其相关风险的评估仍研究不足。在这种情况下，采用可培养和分子方法评估了刚果民主共和国金沙萨市水生环境中细菌和抗生素耐药基因的传播。可培养方法量化了河流沉积物和接收未经处理的医院废水的地表水的β-内酰胺、碳青霉烯类耐药和总大肠杆菌和肠杆菌科。分子方法利用定量聚合酶链反应 (qPCR) 来量化沉积物样本中的总细菌和相关细菌（大肠杆菌、肠球菌和假单胞菌）的丰富度，以及抗生素耐药基因（ARGs：bla、bla、bla、bla）。采用统计学分析来强调医院对水生生态系统中细菌和 ARGs 的贡献以及季节性变化的重要性，这些细菌和 ARGs 位于金沙萨的郊区城市。与雨季相比，旱季医院对抗生素耐药性传播的贡献更高（p<0.05）。在两个季节中，医院同样对沉积物中大肠杆菌、肠球菌和假单胞菌以及 ARGs 有显著贡献（p<0.05）。有机物含量与大肠杆菌呈正相关（r=0.50，p<0.05）。总细菌负荷与肠球菌和假单胞菌呈正相关（0.49<r<0.69，p<0.05）。每个 ARG 与总细菌负荷或至少一种相关细菌呈正相关（0.41<r<0.81，p<0.05）。我们的研究结果证实，医院废水对抗生素耐药谱有显著贡献，这种贡献在旱季增加。此外，我们的分析强调了发展中国家未经处理的医院废水所带来的这种风险，这对公共卫生构成了巨大威胁。
