Volume 24, Number 12—December 2018
Research
Highly Pathogenic Clone of Shiga Toxin–Producing Escherichia coli O157:H7, England and Wales
Figure 2

Figure 2. Timed phylogeny of Shiga toxin–producing Escherichia coli O157:H7 sublineage IIb isolates illustrating the sequential loss of stx2c and subsequent gain of stx2a. Scale bar indicates years in the past.
1These first authors contributed equally to this article.