A drug-resistant type of bacteria that has adapted to health care settings evolved in the past several years to weaponize an antimicrobial genetic tool, eliminating its cousins and replacing them as the dominant strain. University of Pittsburgh School of Medicine scientists made the discovery when combing through local hospital data—and then confirmed that it was a global phenomenon.

The finding, published in Nature Microbiology, may be the impetus for new approaches in developing therapeutics against some of the world’s deadliest bacteria. It also validates a new use for a system developed at Pitt and UPMC that couples genomic sequencing with computer algorithms to rapidly detect infectious disease outbreaks.

“Our lab has a front row seat to the parade of pathogens that move through the hospital setting,” said senior author Daria Van Tyne, Ph.D., associate professor of medicine in Pitt’s Division of Infectious Diseases. “And when we took a step back and zoomed out, it quickly became apparent that big changes were afoot with one of the world’s more difficult-to-treat bacteria.”