Multiple Distinct Outbreaks of Panton-Valentine Leukocidin (PVL)-Positive Community-Associated Methicillin-Resistant Staphylococcus aureus (CA-MRSA) in Ireland Investigated by Whole-Genome Sequencing

Forty-six suspected outbreak-associated isolates from 36 individuals at three separate Irish hospitals (H1-H3) and in two families associated with H2 were investigated by whole genome sequencing (WGS) and whole-genome multilocus sequence typing (wgMLST).Two independent PVL-positive ST8-MRSA-IVa MRSA infection outbreaks in two Dublin-based hospitals were shown to be unrelated by wgMLST, a protracted PVL-positive ST5-MRSA-IVc outbreak in a Dublin-based teaching hospital was revealed and the intra-familial transmission of PVL-positive ST1-MRSA-V+fus+tirS+ccrA1 and PVL-negative ST97-MRSA-V+fus isolates in two separate families was identified.