A recent US study revealed that pathogens in dolphins, like in humans, have developed a resistance to antibiotics.
Antibiotic resistance is one of the biggest public health challenges in the world today since many common bacterial infections are developing resistance to the drugs once used to treat them. New antibiotics should be developed fast enough to combat the issue.
Researchers from Florida Atlantic University's Harbor Branch Oceanographic Institute in collaboration with Georgia Aquarium, the Medical University of South Carolina and Colorado State University, have worked together to answer one question: Do species, other than humans, suffer from this problem?
A report published Sunday by the Florida Atlantic University's website, said this answer required 13 years of research. The researchers captured the dolphins June and July each year (from 2003 to 2015). They took samples from the blowhole, gastric fluid and feces and returned the dolphins to their home in Florida's Indian River Lagoon.
Scientists obtained a total of 733 pathogen isolates from 171 dolphins. Several of the organisms isolated from these animals are important human pathogens. The most frequently isolated pathogens were Aeromonas hydrophila, E. coli, Edwardsiella tarda, V. alginolyticus, and S. aureus.
During the study, these bacteria isolations were cultured on standard media under aerobic conditions. They saw efficiency tests of antibiotics such as erythromycin, ampicillin, and cephalothin. The findings published recently in the Aquatic Mammals journals showed that the overall resistance to antibiotics was 88.2 percent.
The prevalence of resistance was highest to erythromycin (91.6 percent), followed by ampicillin (77.3 percent) and cephalothin (61.7 percent).
Adam M. Schaefer, lead author and an epidemiologist at FAU's Harbor said: "In 2009, we reported a high prevalence of antibiotic resistance in wild dolphins, which was unexpected. Since then, we have been tracking changes over time and have found a significant increase in antibiotic resistance in isolates from these animals."
"This trend mirrors reports from human health care settings. Based on our findings, it is likely that these isolates from dolphins originated from a source where antibiotics are regularly used, potentially entering the marine environment through human activities or discharges from terrestrial sources," he added.