Role of accessory genome in the surge and decline of vanA vancomycin resistant Enterococcus faecium ST80 in Denmark

Vancomycin resistant Enterococcus faecium (VREfm) ST80, formerly the predominant vanA-positive hospital-associated clone in Denmark, declined over the past decade as it diversified genomically. In this study, analysis of 334 isolates from 2012-2020 showed the emergence of multiple sub clusters driven by both recombination events and the dynamic loss or gain of genes involved in general metabolism, antibiotic resistance and virulence, and inter-clonal competition.