INTERACT - The interaction of metals and biocides with the selection of antibiotic-resistant bacteria

Research Project, 2013 – 2017

Multi-resistant bacteria cause tens of thousands of deaths every year in Europe, jeopardizing all kinds of medical procedures. According to the WHO, the rapid resistance development is one of the largest threats to public health, globally. Alarmingly, not only antibiotics select for resistance, but the combined exposure to biocides and metals can also contribute through coselection and cross-resistance. Chemicals in the environment may thus make bacteria untreatable with antibiotics at a later stage. To enable mitigations, INTERACT will identify chemicals and environments associated with high risks for combination effects. Specifically, we will assess: 1) what biocides and concentrations that promote resistance development; 2) in which environments high-risk mixtures can be found; 3) the genetic basis for co- and cross-resistance; 4) the potential for resistance factors to spread from the environment to human pathogens? We will combine controlled laboratory experiments with field studies. Sequencing of community DNA, competition and community tolerance experiments will be used to assess selection pressures and resistance mechanisms for a range of biocides, environments and mixtures. Fluorescent bacteria will be used to assess horizontal gene transfer potential. State-of-the-art chemical analyses will allow description of mixture exposure. INTERACT will provide crucial input to environmental regulatory agencies, as well as the health care, water and shipping sectors.