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Gulls as sources of environmental contamination by colistin-resistant bacteria

March 10, 2020

In 2015, the mcr-1 gene was discovered in Escherichia coli in domestic swine in China that conferred resistance to colistin, an antibiotic of last resort used in treating multi-drug resistant bacterial infections in humans. Since then, mcr-1 was found in other human and animal populations, including wild gulls. Because gulls could disseminate the mcr-1 gene, we conducted an experiment to assess whether gulls are readily colonized with mcr-1 positive E. coli, their shedding patterns, transmission among conspecifics, and environmental deposition. Shedding of mcr-1 E. coli by small gull flocks followed a lognormal curve and gulls shed one strain >101 log10 CFU/g in their feces for 16.4 days, which persisted in the environment for 29.3 days. Because gulls are mobile and can shed antimicrobial-resistant bacteria for extended periods, gulls may facilitate transmission of mcr-1 positive E. coli to humans and livestock through fecal contamination of water, public areas and agricultural operations.

Citation Information

Publication Year 2020
Title Gulls as sources of environmental contamination by colistin-resistant bacteria
DOI 10.1038/s41598-020-61318-2
Authors Alan B. Franklin, Andrew M. Ramey, Kevin T Bentler, Nicole L Barret, Loredana M McCurdy, Christina Ahlstrom, Jonas Bonnedahl, Susan A. Shriner, Jeffrey C Chandler
Publication Type Article
Publication Subtype Journal Article
Series Title Scientific Reports
Index ID 70210283
Record Source USGS Publications Warehouse
USGS Organization Alaska Science Center Biology WTEB