The purpose of this study is to develop a real-time diagnostic technique with e- Ab sensor for influenza virus detection, the investigators conduct a prospective clinical study. In comparison with results from direct sequencing of influenza virus, the investigators evaluate the performance of e- Ab sensor, including reproducibility, sensitivity, specificity, and cross-reaction. The potential factors which may interfere with the results would be investigated. With such technique, the investigators hope to make early diagnosis and give influenza virus patients early treatment to reduce the complications and case-fatality rate.