Antimicrobial Resistance Genes and Wastewater Treatment

Abstract

The global use of antibiotics at low cost, auto medication, and short duration of treatment has accelerated, extended, and expanded the spectra of resistance worldwide. Aquatic ecosystems have been identified as hotspots of resistance mechanisms. This is due to the large diversity of pathogenic and commensal microorganisms and the continuous discharge of antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs) into these environments. As part of aquatic ecosystems, urban wastewater treatment systems (collecting sanitary sewage, hospital effluents, and storm water runoff) possess all the components required to ensure the acquisition of all varieties of resistance genes. The antimicrobials present in wastewater due to incomplete degradation by humans and animals, disposal of unused drugs, and runoff losses from land application, together with environmental and pathogenic bacteria in nutrient-rich engineered systems, provide all the necessary requirements to support a breeding ground for horizontal gene transfer and the propagation of resistance genes.