Rapid diagnosis of influenza: state of the art.

Much effort has been expended developing testing modalities for influenza viruses that are capable of providing rapid results to clinicians. Antigen-detection techniques, historically the only methods able to deliver results quickly, are still widely used despite concerns about sensitivity. Recently, nucleic acid amplification tests (NAATs), which can achieve rapid turnaround times and high sensitivity, have become available. In addition, NAATs can detect other respiratory pathogens. Although there are many theoretical advantages to rapid influenza testing, the clinical impact of testing in various patient populations must be considered against the cost and the analytical performance of the tests.