SRA

We sought to sequence and analyse colonized or infected patients from February 2012 to September 2018 thought to be involved in several patient clusters. 76 patients with MDR Ab were identified and 82 isolates collected. Most isolates sequenced belonged to global clone 2 (GC2) where we found nine WGS clusters. In-depth analysis of clusters showed that in six of them a recent transmission was likely. Clusters were clearly distinct (> 105 SNPs), however, we also identified one clade which included several transmission chains, each separated by an intermediate number of SNPs (20-50). Among the non-GC1/GC2 isolates we found two WGS clusters indicating a recent transmission. No transmission events were detected in GC1. WGS followed by analysis of epidemiological data and further in-depth contact tracing analysis supported the investigation of possible transmission links, highlighting the central role of our tertiary care hospital within a network of other hospitals and rehabilitation centres. Improvement of surveillance strategies and early sequencing is needed in situations with high patient referral between hospitals and rehabilitations centres, in order to eliminate the risks of epidemic as well as endemic MDR clones as a potential risk for future outbreaks.