Figure 2.

Genomic epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) isolates collected at intake to the jail. A, An unrooted maximum likelihood phylogenetic tree showing isolates from all study individuals colonized with MRSA on admission to Cook County Jail. Tips are colored according to inferred strain type (USA300, USA500, and ST5). The branch leading to ST5 is truncated for display purposes, with the length of the branch overlaid on the truncated branch. B, A rooted representation of the tree from panel A is shown, with branch lengths ignored for visualization purposes. Clades corresponding to the 3 strain types are indicated by color, and the shapes in the outer rings indicate the epidemiologic characteristics of MRSA-colonized individuals. Filled circles, squares, and stars indicate that the corresponding individual is living with HIV, reports being a MSM, or has a history of methamphetamine use, respectively. Abbreviations: HIV, human immunodeficiency virus; MSM, man who has sex with men.