Climate change and antimicrobial resistance: converging threats for wildlife

Antimicrobial resistance (AMR) is a complex ecological problem that has expanded beyond people to include animals (domesticated and wildlife) and the environment. The connectivity between people and other animals within shared environments and the transmission of antimicrobial-resistant pathogens across these three dimensions demonstrates the necessity for One Health systems approaches to manage and mitigate AMR. The ecological AMR system now encompasses climate change which can impact microbial factors, host factors, and environmental factors, presenting more complex problems for AMR mitigation. Wildlife species are now well integrated in AMR ecology with detections of diverse antibiotic resistance genes and resistant microbes in many species of birds, reptiles, marsupials and placental mammals. Importantly, many wildlife hosts have also never received antimicrobials. Whole genome sequencing of antimicrobial resistant bacteria isolated from wildlife indicates that wildlife acquire antimicrobial-resistant microbes via anthropogenic contaminated environments. Climate change is already a significant threat to wildlife globally, with mounting evidence that climate hazards are also driving increased prevalence and diversity of antimicrobial resistance in wildlife. Importantly, to avoid masking the complex nature of environmental AMR pollution and climate change for wildlife health, communication of primary AMR drivers should not continue to focus on, and be limited to, use and misuse of antimicrobials in people and agriculture. Recognising the importance of climate change for AMR ecology is vital for advancing One Heath strategies for AMR mitigation and wildlife protection.