Populations of antibiotic-resistant coliform bacteria change rapidly in a wastewater effluent dominated stream

Wastewater Treatment Effluent Reduces the Abundance and Diversity of Benthic Bacterial Communities in Urban and Suburban Rivers

“…There is growing concern about the presence of a wide range of biologically active compounds, including antimicrobials, in rivers and streams receiving WWTP effluent in the United States (44). Many of these compounds are not completely removed by wastewater treatment, so WWTPs are point sources of these compounds (45,46). If the effluent from the two WWTPs examined in this study contained compounds toxic to microorganisms (both algae and bacteria), this could explain both the decrease in bacterial numbers and the decrease in concentrations of sediment organic matter.…”

Conjugative transmission of antibiotic-resistance from stream waterEscherichia colias related to number of sulfamethoxazole but not class 1 and 2 integrase genes

“…14 Previously, Escherichia coli containing plasmids were recovered from wastewater treatment plant (WWTP) effluent and receiving stream water in Northwest Arkansas that were phenotypically resistant to one to up to 5 different antibiotics. 15,16 A subset of isolates expressing resistance to sulfamethoxazole and trimethoprim were found to possess redundancy and a diversity among sulfamethoxazole resistance (sul) or trimethoprim resistance (dfr) genes, respectively. 17 These sul and dfr and other antibiotic resistance genes might be associated with conjugative and/or mobilizable plasmids and integrons, which were also found to be abundant among resistant isolates, 18 promoting dissemination of the antibiotic resistance determinants.…”

“…As many as 69% (9 out of the 13 which did not produce transconjugants) harbored multiple plasmids in individual organisms. 16 Otherwise, the isolates had little in common, the E. coli exhibited between one and 4 phenotypic resistances, were sampled from longitude). Antibiotic resistances were determined for the stream water (donor) E. coli at the following concentrations for a total of 6 different antibiotics: 32 mg/mL ampicillin, 16 mg/mL gentamicin, 16 mg/mL tetracycline, 8 mg/mL ofloxacin, 4 mg/mL trimethoprim, and 80 mg/mL sulfamethoxazole.…”

Destruction of <i>Escherichia coli</i> and Broad-Host-Range Plasmid DNA in Treated Wastewater by Dissolved Ozone Disinfection under Laboratory and Field Conditions

“…While the processes employed at modern wastewater treatment facilities in the United States and in other industrialized countries are considerably evolved, the final effluent leaving these plants is not completely free of biological and chemical materials that are potentially harmful to humans and the environment [1][2][3][4]. Of developing concern are bioreactive compounds that are not targeted by regulations governing discharge of wastewater.…”

“…An obvious threat to public health is disease from pathogens that may persist in the environment after release. A less obvious threat is genetic determinants that can provide antimicrobial resistance phenotypes to pathogenic populations, such as antibiotic resistance genes contained on bacterial plasmids and other mobile genetic elements [1,9,10]. In particular, broad-host-range plasmids have several attributes contributing to concerns about their control: they can carry genes coding for resistance to multiple antibiotics and metals [11]; they can be stably maintained within and transferred among diverse bacterial taxa [12][13][14]; and they can persist outside of the cell for possible later uptake and expression by bacterial hosts [15].…”