Pre- and post-travel E. coli from each volunteer indicating CTX-M-EC, non-CTX-M-EC, and toothpicked strainsa

  • a Gray shading indicates data from toothpicking experiments.

  • b Standard font indicates non-CTX-M; boldface indicates CTX-M-15; italic indicates CTX-M-14.

  • c Text in parentheses, e.g., “(3/3a),” indicates the number of toothpicked colonies which were sequenced, followed by the fecal sample number.

  • d ST2617, non-CTX-M-EC, in fecal sample 9f, is not the same strain as the CTX-M-producing ST2617, also from volunteer 9 feces (after SNP typing).

  • e NT, non-typeable.