Gulls as Sources of Environmental Contamination by Colistin-resistant Bacteria

Authors

• Alan B. Franklin, USDA-APHIS-WS National Wildlife Research CenterFollow
• Andrew M. Ramey, USGS Alaska Science Center, AnchorageFollow
• Kevin T. Bentler, NWRC APHIS USDAFollow
• Nicole L. Barrett, NWRC APHIS USDA
• Loredana M. McCurdy, NWRC APHIS USDA
• Christina A. Ahlstrom, USGS Alaska Science Center, AnchorageFollow
• Jonas Bonnedahl, Linköping University, SwedenFollow
• Susan A. Shriner, USDA/APHIS/WS National Wildlife Research CenterFollow
• Jeffrey C. Chandler, NWRC APHIS USDAFollow

ORCID IDs

Alan B. Franklin http://orcid.org/0000-0001-9491-795X

Christina A. Ahlstrom http://orcid.org/0000-0001-5414-8076

Document Type

Article

Date of this Version

2020

Citation

Scientific Reports (2020) 10:4408

doi 10.1038/s41598-020-61318-2

Comments

This article is licensed under a Creative Commons Attribution 4.0 International License

Abstract

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.