Multiple major disease-associated clones of Legionella pneumophila have emerged recently and independently

Maximum clade credibility tree of the ST37 lineage showing the estimated age of the MRCA. A time-dependent phylogenetic reconstruction of the ST37 lineage, inferred by Bayesian inference using BEAST, is shown. The Philadelphia isolate (a single locus variant of ST37) was also included in the analysis as an out-group. The node representing the MRCA of the ST37 lineage is labeled with the median estimate for the inferred date and the 95% highest posterior probability (HPD) intervals. Isolates are colored according to the country of isolation, and branches are similarly colored to indicate the origin of descendant nodes.