blaNDM-5-positive and mcr-9-carrying Escherichia coli lineages in wild Andean condors feeding at landfills in South America.

Clinically relevant antibiotic-resistant bacteria are increasingly detected in natural environments, reinforcing the need for a One Health approach that recognizes the interconnectedness of human, animal, and environmental health. We investigated the occurrence of World Health Organization critical-priority carbapenem-resistant Enterobacterales in 1000 wildlife samples collected across Chilean ecoregions, including the Andean Highlands, Antarctica, the Atacama Desert, the Chiloé Archipelago, and Patagonia. Carbapenem-resistant Enterobacterales were detected in 5 samples, all recovered from wild Andean condors (Vultur gryphus) feeding at landfills at the foothills of the Andes Mountains. Genomic analyses identified multidrug-resistant carbapenem-resistant Escherichia coli carrying blaNDM-5 and, in two isolates, mcr-9. These isolates belonged to sequence types 46, 345, 744, and 2973 and carried broad resistomes to β-lactams, aminoglycosides, fluoroquinolones, sulfonamides, trimethoprim, phenicols, and tetracyclines, together with genes associated with disinfectants and heavy metals. These findings highlight exposure of wild Andean condors to clinically relevant carbapenem-resistant E. coli in landfill-associated environments and support the need for preventive measures to reduce wildlife contact with anthropogenic waste.