Initial detection and reporting by clinical microbiology laboratories is a sentinel marker for foodborne outbreak surveillance systems. Initiation of a public health investigation is reliant on the rapid initial identification of pathogens of interest. Diagnostics for Escherichia coli have evolved to reduce identification turnaround time, incorporating technologies for rapid identification (MALDI-TOF MS) and serogrouping (O157 antiserum or latex agglutination). Reporting of these isolates to a public health agency may initiate further laboratory investigations, such as pulsed-field gel electrophoresis, for confirmation that isolates may be related to a common source (clonal population).