Figure 2. Phylogeny of Salmonella 1,4,,12:i:- epidemic clade isolates from the United Kingdom and Italy, 1993–2010. Maximum-likelihood tree of 77 Salmonella 1,4,,12:i:- isolates rooted with Salmonella Typhimurium strain SL1344 was constructed by using 1,058 single-nucleotide polymorphisms (SNPs) outside of prophage elements, insertion sequence elements, and sequence repeats identified with reference to whole-genome sequence of Salmonella Typhimurium strain SO4698-09. Bootstrap values <70 are indicated at nodes. Subclades A (blue lineages), B (red lineages), and C (green lineages) are indicated. Strain designations are color coded for isolates from humans (red) and animals (blue). Epidemiologic data for the source of isolate, phage type, country of origin, presence of the virulence plasmid (pSLT), presence of the sopE gene, occupancy of the thrW locus, and presence of Salmonella genetic island 3 are indicated (right). Scale bar indicates the approximate number of SNPs determined by genetic distance and the number of SNPs used to construct the tree.