Drug-resistant bacteria evolve to dominate healthcare settings

Scientists have discovered that a drug-resistant bacteria known as vancomycin-resistant Enterococcus faecium (VREfm) has evolved to eliminate its competitors in healthcare settings. This breakthrough was made by researchers at the University of Pittsburgh School of Medicine after analyzing hospital data. The study, published in the journal Nature Microbiology, found that VREfm strains have shrunk from eight types in 2017 to just two dominant strains by 2022. These new strains have developed the ability to produce antimicrobial agents called bacteriocins, which help them kill off other VREfm strains, allowing them to thrive. Lead researcher Emma Mills focused on VREfm due to its high mortality rate, especially in hospitalized patients. While this bacteria is resistant to the common antibiotic vancomycin, the new findings suggest potential new strategies for treating infections caused by it. Mills’ analysis of over 700 samples showed a dramatic change in VREfm's population, leading her to investigate if this trend was happening globally. She explored a database of more than 15,000 VREfm genomes and confirmed that similar patterns were occurring worldwide. Although this research does not indicate that the new strains are making patients sicker than before, it does suggest that the narrowing diversity of VREfm could lead to new therapeutic targets for future treatments. Researchers believe that understanding and potentially using bacteriocins could provide innovative approaches to combat drug-resistant bacteria.