 Consenting subjects will have a nasopharyngeal NP swab collected for both Xpert Flu testing and gold standard reverse transcription-PCR rt-PCR testing under a research protocol. The investigators will compare the test results from the rapid flu testing to that of the gold standard rt-PCR testing in order to assess the clinical performance characteristics of the new rapid test Objective 1. The investigators will also collect demographics and medical historical information using a brief structured data form, which will be used in combination with rt-PCR test results to derive and validate a clinical decision guideline Objective 2. 