Factors influencing antimicrobial resistance in the European food system and potential leverage points for intervention: A participatory, One Health study.

Introduction: Antimicrobial resistance (AMR) is a global crisis that evolves from a complex system of factors. Understanding what factors interact is key to finding solutions. Our objective was to identify the factors influencing AMR in the European food system and places to intervene.
Materials and Methods: We conducted two workshops involving participants with diverse perspectives to identify the factors influencing AMR and leverage points (places) to target interventions. Transcripts were open coded for factors and connections, then transcribed into Vensim 8.0.4 to develop a causal loop diagram (CLD) and compute the number of feedback loops. Thematic analysis followed to describe AMR dynamics in Europe's food system and places for intervention. The CLD and themes were confirmed via participant feedback.
Results: Seventeen participants representing human, animal and agricultural sectors identified 91 CLD factors and 331 connections. Seven themes (e.g., social and economic conditions) describing AMR dynamics in Europe's food system, five 'overarching factors' that impact the entire CLD system (e.g., leadership) and fourteen places for intervention (e.g., consumer demand) emerged from workshop discussions. Most leverage points fell on highly networked feedback loops suggesting that intervening at these places may create unpredictable consequences.
Conclusions: Our study produced a CLD of factors influencing AMR in Europe's food system that implicates sectors across the One Health spectrum. The high connectivity between the CLD factors described by participants and our finding that factors are connected with many feedback mechanisms underscores the complexity of the AMR problem and the challenge with finding long-term solutions. Identifying factors and feedbacks helped identify relevant leverage points in the system. Some actions, such as government's setting AMU standards may be easier to implement. These actions in turn can support multi-pronged actions that can help redefine the vision, values and goals of the system to sustainably tackle AMR.
Competing Interests: I.A.L., M.C., T.G., A.L., S.H., D.W., P.S.J., and E.J.P. have no competing interests to declare. P.H. is a member of the Technical Committee for the BAP Vanguard Climate Action Standard and P.H. and M.T. act as scientific advisors to the Seafood Business for Ocean Stewardship (SeaBOS) initiative. P.H. was supported by the CGIAR Research Program on Fish Agri-Food Systems (FISH) led by WorldFish and on Climate Change, Agriculture and Food Security (CCAFS) supported by contributors to the CGIAR Trust Fund. P.H. and M.T. acknowledge the Kjell and Märta Beijer Foundation for supporting this work through the Beijer Institute’s Aquaculture and Sustainable Seafood programme, and the SEAWIN project funded by FORMAS (2016-00227). P.H. is partially funded by FORMAS Inequality and the Biosphere project (2020-00454). A.P.D. is (or has been in the last 5 years) engaged in research grants funded by the Sustainable Aquaculture Innovation Centre, UK Research and Innovation, International Veterinary Vaccinology Network, Scottish Funding Council, Great British Prawns Ltd and Benchmark Animal Health. C.A.C. works for the Government of Canada at the Public Health Agency of Canada. C.A.C. is/has been a subject matter expert for the World Organisation for Animal Health (OIE) and the World Health Organization (WHO) and has been a co-topic editor for two volumes of a Frontiers in Veterinary Science, Research Topic: Antimicrobial Usage in Companion and Food Animals: Methods, Surveys and Relationships with Antimicrobial Resistance in Animals and Humans. S.E.M. is (or has been in the last 5 years) engaged in research grants/contracts funded by the Canadian Institutes for Health Research, the Bill and Melinda Gates Foundation/UK Dept., International Development, the Natural Sciences and Engineering Research Council of Canada, Institut de recherche Robert-Sauvé en santé et en sécurité du travail, Dairy Farmers of Canada Research Funding Program, the World Health Organization, British Columbia Centre for Disease Control, Indian and Northern Affairs Canada, and Ontario Ministry of Agriculture, Food and Rural Affairs. She currently sits on the Editorial Boards of Foodborne Pathogens and Disease, and Epidemiology and Infection, and is a member of the World Health Organization’s Foodborne Disease Burden Epidemiology Reference Group, and she has served as a paid expert on behalf of the Attorney General of Canada in legal proceedings, providing evidence on the public health risks and benefits of unpasteurized milk. This does not alter our adherence to PLOS ONE policies on sharing data and materials.