Antibiotic-Resistance Genes in Waste Water

Waste water and waste water treatment plants are potential hot spots of selection of antibiotic resistance and horizontal gene transfer. Hospitals are only a small proportion of the sources of antibiotics, antibiotic-resistant bacteria (ARB), and antibiotic-resistance genes (ARGs); municipal wastes are also vital sources. Mobile genetic elements are likely to play a role in the dissemination of antibiotic resistance in waste water. The detection of an ARG does not mean that this is conferring resistance in the host. Thus, molecular methods are needed that can distinguish between ARG carriage in the host chromosome and ARG which confers resistance or a risk to the treatment of pathogens. Waste waters contain traces of antibiotics and other compounds which can cause a selection pressure for antibiotic resistance, and even low concentrations are able to cause selection pressure. Waste water and waste water treatment plants can act as reservoirs and environmental suppliers of antibiotic resistance. They have also been proposed to be hotspots for horizontal gene transfer, enabling the spread of antibiotic resistance genes between different bacterial species. Waste water contains antibiotics, disinfectants, and metals which can form a selection pressure for antibiotic resistance, even in low concentrations. Our knowledge of antibiotic resistance in waste water has increased tremendously in the past few years with advances in the molecular methods available. However, there are still some gaps in our knowledge on the subject, such as how active is horizontal gene transfer in waste water and what is the role of the waste water treatment plant in the environmental resistome? The purpose of this review is to briefly describe some of the main methods for studying antibiotic resistance in waste waters and the latest research and main knowledge gaps on the issue. In addition, some future research directions are proposed. Waste water and waste water treatment plants can act as reservoirs and environmental suppliers of antibiotic resistance. They have also been proposed to be hotspots for horizontal gene transfer, enabling the spread of antibiotic resistance genes between different bacterial species. Waste water contains antibiotics, disinfectants, and metals which can form a selection pressure for antibiotic resistance, even in low concentrations. Our knowledge of antibiotic resistance in waste water has increased tremendously in the past few years with advances in the molecular methods available. However, there are still some gaps in our knowledge on the subject, such as how active is horizontal gene transfer in waste water and what is the role of the waste water treatment plant in the environmental resistome? The purpose of this review is to briefly describe some of the main methods for studying antibiotic resistance in waste waters and the latest research and main knowledge gaps on the issue. In addition, some future research directions are proposed.