STRESST is a project where training of healthcare personnel in antimicrobial stewardship is aimed to counteract over-use and wrong use of antibiotics in hospitals. The project will follow changes in abundance of both antibiotics themselves and resistant bacteria in hospital wastewater before, during and after stewardship training. Transmission of the resistant bacteria detected will be tested in the laboratory for their capability to be transferred from one type of bacteria to another, in a way which is likely to occur in wastewater with high content of antibiotics.
Our STRESST project (Antimicrobial Stewardship in Hospitals, Resistance Selection and Transfer in a One Health Context) will determine the effects of hospital-wide antimicrobial stewardship on the amount of antibiotics, and the numbers of susceptible and resistant bacteria, released in hospital wastewater. This data will show if stewardship can reduce the amounts of antibiotics and resistant bacteria entering the environment. Hospital wastewater is also likely to represent a hotspot for selection of antibiotic resistant bacteria. We will determine if the antibiotics present can catalyse both intracellular transposition and intercellular conjugation of mobile genetic elements carrying antibiotic resistance genes, and if this is less likely to occur following the antimicrobial stewardship intervention. In addition to agar plate-based assays, these experiments will also include state of the art animal caecum fermenter models which will directly link the healthcare environment (hospital) with the wider environment (via hospital wastewater) and animal health representing all three One Health areas. Ultimately, the STRESST project will demonstrate the effectiveness of antimicrobial stewardship in reducing antibiotic, and antibiotic resistant bacteria, release into the environment and how this impacts resistance transmission within and between microbial communities present in animals that use this as a water source. This holistic view of resistance transmission within a One Health context will serve to highlight a selection hotspot (hospital wastewater) for future interventions.