Fig. 1

a Hierarchical cluster based on observed differences in the MALDI-TOF peak profile of cultures grown for 48 h. Indicated are the year of isolation for isolates A-H and the two outbreak clusters I and II. b SNP variant phylogenetic tree of sequenced isolates. The genome of isolate F was used as reference for the phylogeny. Scale bar indicates numbers of SNP differences between the isolates. Isolates H, A/B and G map to only 89, 76 and 77% of the reference genome, respectively