Carolina from 2009 to 2010 were utilized in the project. Based upon a previous analysis of emergency department (ED) presentations, an interdisciplinary team (EMS, emergency department, epidemiology and public health) then developed an approach to assign EMS records to 1 of the 20 symptom-based illness categories (gastrointestinal illness, respiratory, etc). EMS encounter records were characterized into these illness categories using a novel text analytic program (SAS Institute, Cary, NC). Baseline patterns of EMS encounters were developed for each illness category across the state, local regions (3-digit zip code) over time. Event alerts were identified across the state and by regions in illness categories using either change detection with cumulative sum (CUSUM) analysis (3 standard deviations) or a novel text-proportion (TAP) analysis approach (SAS Institute).