Volume 24, Number 3—March 2018
Dispatch
Statistical Method to Detect Tuberculosis Outbreaks among Endemic Clusters in a Low-Incidence Setting
Figure 2

Figure 2. Whole-genome sequencing results for a prevalent (endemic) cluster detected as a possible tuberculosis outbreak, United States, 2009–2016. Values indicate number of SNPs. Shown is a closely related (<2 SNPs) group of 11 isolates (lower section of phylogenetic tree). Isolates reported during a 3-year window of unexpected growth are indicated in gray. One isolate reported 1 quarter before and 1 isolate reported 1 quarter after the 3-year window of unexpected growth detection are indicated in white. An additional 2 isolates were 3 SNPs from this closely related group, 1 during (gray) and 1 outside (white) the unexpected growth window. MRCA, most recent common ancestor; SNP, single-nucleotide polymorphism.