Targeted removal of ARGs and facultative pathogenic bacteria in wastewater from AMR hotspots using modular advanced treatment solutions

The goal of the HOTMATS project is to develop and demonstrate effective and compact technical solutions for source treatment of wastewater from key point sources that release antimicrobial resistance (AMR). The aim is to stop the spread of antibiotic-resistant bacteria (ARB), antibiotic resistance genes (ARG), and other health-threatening microorganisms from AMR point sources before they are released into the municipal wastewater system. Currently, the wastewater system is one of the main pathways for the transport of ARB and ARG between the three pillars of One Health, i.e., human, animal, and environmental health, while the infrastructure is often old and leaking. The intervening solutions to be developed in HOTMATS will help reduce the load of AMR to the wastewater network and at municipal wastewater treatment plants, thereby reducing the release of ARB and ARG to the environment. This will help minimize the uncontrolled spread of AMR to recipients, thus preventing potential re-transfer of resistance to patients and healthcare institutions. HOTMATS investigates the suitability of various principles for wastewater treatment, designs new systems for wastewater treatment, and demonstrates the destruction of both ARB and ARG in contaminated wastewater from hospitals. Three pilot systems employing the different treatment principles of ozone disinfection, UV light, and filtration were developed, and their effectiveness in destroying ARB and ARG in concentrated wastewater streams from a hospital is being tested. The investigated solutions are intended to be more effective, have a smaller footprint, and consume less energy and resources compared to existing methods. This makes them attractive for use as intervening solutions at point sources, either retrofitted, integrated into old building infrastructure, or at sites with limited space. During the project, three pilot plants for ozone disinfection, UV light, and filtration were designed and installed at the VEAS wastewater treatment plant. Untreated wastewater from the intensive care and cancer departments at Ullevål Hospital was collected and transported by suction truck to the pilot plants. Several tests were conducted, where the purification capacity of the ozonation and UV pilots was quantified. During the tests, various ozone concentrations were tested, and relevant resistance genes from pathogenic, so-called ESKAPE bacteria, which indicate AMR, were analyzed. The results show effective purification of the indicator genes, with a reduction greater than 90%. UV combined with ozonation gave better results than ozonation alone. The results were presented at several conferences. The filtration plant is now completed and will be connected to the other two plants. In HOTMATS, we are also developing a new purification method based on light irradiation of wastewater. The method for inactivating ARB and ARG in wastewater from hospitals, wastewater treatment plants, and slaughterhouses is currently being tested in collaboration with our German and Ghanaian partners. The overarching goal is to increase the removal rate of ARB and ARG through various combinations of technologies (so-called ‘multi-barrier’ for wastewater treatment), which alone are not effective enough. Some of the work has been published and an article on a more advanced application is currently being written. The transfer of knowledge, methods, and technology from high-income countries to low- and middle-income countries constitutes a significant part of the HOTMATS project. Additionally, we highlight socio-economic cost-benefit aspects related to the application, costs, and benefits of the technologies developed in HOTMATS. This is done in collaboration with our African partners.

Goal of HOTMATS is to design, implement and assess modular advanced solutions for effective and decentralized wastewater treatment at selected point sources of antimicrobial resistance (AMR) emergence to minimize AMR spread into the environment. The applied technologies are primarily targeting AMR pollution and pathogens in wastewater streams directly at AMR hotspots. HOTMATS moves away from ‘end-of-pipe’ approaches applied at wastewater treatment plants and address intervention in all three pillars of One-Health. The treatment principles of the used technical solutions are based on combined ozonation/advanced oxidation process, UV-C irradiation, photolysis, and membrane filtration. The superiority of the novel pilot-scale treatment systems as opposed to state-of-the art solutions will be demonstrated by collecting and treating effluents from AMR hotspots, including a hospital (OUS), nursing homes in Oslo, and slaughterhouses. The approach intends to reduce the risk associated with ARB/ARG/FPB spreading from hotspots to the downstream natural environment, and to unburden central WWTPs from AMR pollution. A cost-benefit analysis will be conducted to demonstrate the potential benefits e.g. avoidance of health risks, and costs adopting the new approaches. The modalities for transferring the technology from HICs to LMICs by conducting a willingness to pay study for uptake of decentralized treatment of AMR in LMICs will also be assessed.