Influenza surveillance for the 2001-03 seasons is being performed at the University of Utah using an electronic medical record on a patient population of -100,000. Influenza epidemics in each season have been identified using multiple statistical process control charts. Signs and symptoms of influenza cases were analyzed and unexpectedly demonstrated significant amounts of abdominal symptoms such as nausea, vomiting, and diarrhea. In influenza cases confirmed by a rapid influenza test, there was not a significant difference between years in the prevalence of reported nausea and vomiting, although there was for diarrhea (15.4% vs. 4.9% [2003 vs. 2002 respectively] p < 0.001). When rapid test positive cases were compared to those not confirmed for 2003, a statistically significant difference was seen (vomiting 25.6% vs. 6.1 %, p<0.05; nausea 23.1 % vs. 9.1 %, p<0.05). Thus far in 2003, patients diagnosed with influenza were statistically less likely to have fever, cough, sore throat, myalgias/arthraigias, headache, chest congestion, sinus pain/pressure, and earache than those diagnosed with influenza in 2002 (all p < 0.001). Other respiratory diagnoses not specifically related to influenza have also been monitored to detect an early influenza epidemic potentially undiagnosed due to cases. The differences in signs and symptoms reporting between years suggests that either influenza presents somewhat differently in different seasons, or many cases may have been misdiagnosed. This finding suggests a need for further research in this area to potentially improve the quality of patient care for influenza.