TOX and diphtheria: SLs and genetic clusters (GCs) as classified by the BIGSdb-Pasteur cgMLST scheme (16) of 144 Ontario C. diphtheriae isolates, together with the geographic location(s) and diphtheria tox gene PCR of other isolates of the same SL, travel histories, and laboratory test results for tox PCR and modified ELEK tests for DT