Orcas can carry antibiotic-resistant, potentially pathogenic strains of E. coli that may come from their environment or food, according to a study led by researchers from the University of Washington School of Public Health.
While more research is needed to determine if this is causing disease that could contribute to the orcas’ decline, “anything potentially pathogenic in their bodies is of grave concern,” said Dr. Marilyn Roberts, a professor in UW’s Department of Environmental & Occupational Health Sciences.
Dr. Roberts, who specializes in antibiotic resistance, and Ms. Daira Melendez, a master’s student in occupational and environmental health, used whole genome sequencing to analyze nine E. coli samples isolated from the feces of Puget Sound’s southern resident orca pods. The researchers identified three antibiotic-resistant genes and segments of a fourth. In people, these strains cause urinary tract disease, but it is not yet known what they do to killer whales.
“This research highlights the importance of One Health and the interrelationship between human, animal and environmental health,” Ms. Melendez said. “The orcas act as sentinels for the health of the Salish Sea — and the effects of pollution caused by humans on marine life.”Friday Letter Submission, Publish on June 28