Genomic comparison of carbapenem-resistant Enterobacteriaceae from humans and gulls in Alaska

Wildlife may harbour clinically important antimicrobial-resistant bacteria, but the role of wildlife in the epidemiology of antimicrobial-resistant bacterial infections in humans is largely unknown. In this study, we aimed to assess dissemination of the bla_KPC carbapenemase gene among humans and gulls in Alaska.

We performed whole-genome sequencing to determine the genetic context of bla_KPC in bacterial isolates from all four human carbapenemase-producing Enterobacteriaceae (CPE) infections reported in Alaska between 2013-2018 and to compare the sequences with seven previously reported CPE isolates from gull faeces within the same region and time period.

Genomic analysis of CPE isolates suggested independent acquisition events among humans with no evidence for direct transmission of bla_KPC between people and gulls. However, some isolates shared conserved genetic elements surrounding bla_KPC, suggesting possible exchange between species.

Our results highlight the genomic plasticity associated with bla_KPC and demonstrate that sampling of wildlife may be useful for identifying clinically relevant antimicrobial resistance not observed through local passive surveillance in humans.