The role of wastewater environments for development and surveillance of antibiotic resistance

The increased prevalence and spread of antibiotic resistant bacteria is a major global threat to public health. Bacterial pathogens can become resistant via mutations or by acquisition of resistance genes from other bacteria through horizontal gene transfer.

We and others have identified wastewater streams and wastewater treatment plants as hot spots for dissemination of antibiotic resistant bacteria to aquatic environments, from where they can spread to humans and cause hard-to-treat infections. In addition, wastewater contains antibiotics and other antibacterial substances at levels that could select for resistant bacteria. Due to the great diversity of bacteria and antibiotic resistance genes present, sewage environments have also been suggested to be hot spots for the emergence of resistant pathogens via horizontal gene transfer. In the group, we combine field studies and lab-based studies in order to investigate the role of wastewater environment in the development of antibiotic resistance.

Wastewater cannot only be a player in the development and transmission of resistant bacteria but could also be an important asset in the fight against antibiotic resistance. One of the cornerstones in this fight is surveillance. The single most important factor for informative surveillance is that sampling reflects a large number of people. Sampling many individuals is costly, cumbersome and requires considerable infrastructure. These are major reasons behind the limited and often complete lack of surveillance of antibiotic resistance in large parts of the world. A single sample of raw wastewater contains excreted bacteria from a large number of individuals. Analyses of such samples have thus the potential to serve as a resource-efficient surveillance system for antibiotic resistance complementing today’s surveillance. In addition, wastewater analyses could also be better suited for detecting rare forms of resistance that are circulating in a population. Our aim is therefore to develop and evaluate a wastewater-based surveillance system for the generation of clinically relevant antibiotic resistance data.

In our research, we combine bacteriological culture-based methods and several molecular biological approaches including long- and short-read DNA sequencing.