摘要

     污水处理厂（WWTPs）是病原微生物群落抗生素耐药性研究的热点。我们观察了斯里兰卡西部、南部两个市政污水处理厂和一个医院污水处理厂中抗生素耐药菌（ARB）、抗生素耐药基因（ARG）和多重耐药菌（MDR）的流行情况，并将结果与印度和世界情况进行了比较，以追踪ARB和ARG的处理印记。结果表明，尽管污水处理导致各污水处理厂的大肠杆菌（E.coli）减少量均高于1.06 log，但对大多数抗生素耐受的大肠杆菌的比例从进水口到出水口有所增加。医院和污水处理厂ARB、ARG和MDR较高的流行率是由于患者使用和排泄的抗生素浓度较高导致的。与印度相比，斯里兰卡的污水处理厂在处理后出现更多的ARB，其比例在持续增加，但很少对对氟喹诺酮（FQ）有抗性。 从两国各地分离的大肠杆菌均表现出多重耐药性，污水处理后耐药性在增加并且与各污水处理厂的FQ密切相关。除了斯里兰卡医院废水中的parC基因外，所有废水中都存在氟喹诺酮（FQ）（aac-（6′）-1bcr、qnrB、qnrS）、β-内酰胺（ampC）和磺胺类药物（sul1）的耐药基因，这意味着对喹诺酮类药物，尤其是环丙沙星的耐药率更高。多变量统计处理表明，出水口出现较多的MDR/ARB，且与MDR/ARB密切相关，处理过程中pH值的变化和与金属的广泛的相互作用可能对此有深远的影响。

      Wastewater treatment plants (WWTPs) are being debated for being the hot spots for the development of antibiotic resistance in pathogenic microbial communities. We observed the prevalence of antibiotic-resistant bacteria (ARB), antibiotic resistance genes (ARG), and multidrug resistance (MDR) in two municipal WWTPs and one hospital WWTP in Western and Southern Sri Lanka, and compared the results with particular reference to Indian and the World scenario to trace the imprints of treatment on ARB and ARG. Result suggests that although wastewater treatment resulted in higher than 1.06 log Escherichia coli (E. coli) reduction at all WWTPs, yet the percent of E. coli resistant to most of the antibiotics increased from influent to effluent. Higher prevalence of ARB, ARG, and MDR were noted in hospital WWTP owing to the higher antibiotic concentrations used and excreted by the patients. With reference to India, the WWTPs in Sri Lanka showed more ARB and a consistent increase in its percentages after the treatment but were less resistant to Fluoroquinolone (FQ). E. coli strains isolated from each location of both countries showed multidrug resistance, which has increased after the treatment and was strongly correlated with FQ in every WWTP. Resistant genes for Fluoroquinolone (FQ) (aac-(6′)-1b-cr, qnrB, qnrS), β-lactams (ampC), and sulphonamides (sul1) were common in all the wastewaters except additional parC gene in the hospital effluent of Sri Lanka, implying much higher resistance for quinolones, especially for Ciprofloxacin. Multivariate statistical treatments suggest that effluent showed higher loadings and association for MDR/ARB, where pH change and more extensive interaction with metals during the treatment processes seem to have profound effects.

     https://www.sciencedirect.com/science/article/abs/pii/S0013935120300712