TY - JOUR AU - Schutz, Kyle AU - Cowley, Lauren AU - Shaaban, Sharif AU - Carroll, Anne AU - McNamara, Eleanor AU - Gally, David AU - Godbole, Gauri AU - Jenkins, Claire AU - Dallman, Timothy T1 - Evolutionary Context of Non–Sorbitol-Fermenting Shiga Toxin–Producing Escherichia coli O55:H7 T2 - Emerging Infectious Disease journal PY - 2017 VL - 23 IS - 12 SP - 1966 SN - 1080-6059 AB - In July 2014, an outbreak of Shiga toxin–producing Escherichia coli (STEC) O55:H7 in England involved 31 patients, 13 (42%) of whom had hemolytic uremic syndrome. Isolates were sequenced, and the sequences were compared with publicly available sequences of E. coli O55:H7 and O157:H7. A core-genome phylogeny of the evolutionary history of the STEC O55:H7 outbreak strain revealed that the most parsimonious model was a progenitor enteropathogenic O55:H7 sorbitol-fermenting strain, lysogenized by a Shiga toxin (Stx) 2a–encoding phage, followed by loss of the ability to ferment sorbitol because of a non-sense mutation in srlA. The parallel, convergent evolutionary histories of STEC O157:H7 and STEC O55:H7 may indicate a common driver in the evolutionary process. Because emergence of STEC O157:H7 as a clinically significant pathogen was associated with acquisition of the Stx2a-encoding phage, the emergence of STEC O55:H7 harboring the stx2a gene is of public health concern. KW - Shiga toxin–producing Escherichia coli serotype KW - outbreak KW - whole-genome sequencing KW - virulence KW - evolution KW - England KW - Ireland KW - STEC O55:H7 KW - bacteria KW - zoonoses DO - 10.3201/eid2312.170628 UR - https://wwwnc.cdc.gov/eid/article/23/12/17-0628_article ER - End of Reference