 The investigators will simultaneously randomize 2 of the 4 hospitals to the Rapid Testing Group which will have systematic rapid flu testing performed with results provided to the clinicians, or the Control Group which will follow standard of care practice with testing left to the discretion of individual clinicians. This will permit comparison of rates of ED antiviral administration or prescription between the two groups to assess the clinical impact of influenza testing Objective 3. Finally, cost data from the ED visits and subsequent hospitalization will be collected from subjects in both the rapid testing group and the control group to inform a cost-utility analysis of rapid influenza testing compared to current standard of care Objective 4. 