Friendly microbes in the intestinal tracts (guts) of healthy American children have numerous antibiotic resistance genes, according to results of a pilot study by scientists at Washington University School of Medicine in St. Louis. The genes are cause for concern because they can be shared with harmful microbes, interfering with the effectiveness of antibiotics in ways that can contribute to serious illness and, in some cases, death.
"From birth to age 5, children receive more antibiotics than during any other five-year time span in their lives," said senior author Gautam Dantas, PhD, assistant professor of pathology and immunology. "Frequent exposure to antibiotics accelerates the spread of antibiotic resistance. Our research highlights how important it is to only use these drugs when they are truly needed."
The results appear Nov. 13 in PLOS ONE.
With funding from the Children's Discovery Institute, the International Center for Advanced Renewable Energy and Sustainability, the National Academies Keck Futures Initiative and the National Institutes of Health (NIH), the researchers analyzed fecal samples from 22 infants and children ranging in age from six months to 19 years. The samples were provided by Phillip Tarr, MD, the Melvin E. Carnahan Professor of Pediatrics at Washington University School of Medicine.
Despite the small sample size, the analysis identified 2,500 new antibiotic resistance genes, expanding the list of known antibiotic resistance genes by more than 30 percent.
"Microbes have been battling each other for millennia, regularly inventing new antibiotic synthesis genes to kill off rivals and new antibiotic resistance genes to defend themselves," Dantas said. "That microbial arms race is where this vast array of genetic resources comes from."
The scientists identified the new resistance genes by testing intestinal microbial DNA from the children against 18 antibiotics. The genes they
|Contact: Michael C. Purdy|
Washington University School of Medicine