Rapid Antigen Tests for Influenza: Rationale and Significance of the FDA Reclassification

Rapid antigen tests for influenza, here referred to as rapid influenza diagnostic tests (RIDTs), have been widely used for the diagnosis of influenza since their introduction in the 1990s due to their ease of use, rapid results, and suitability for point of care (POC) testing. However, issues related to the diagnostic sensitivity of these assays have been known for decades, and these issues gained greater attention following reports of their poor performance during the 2009 influenza A(H1N1) pandemic. In turn, significant concerns arose about the consequences of false-negative results, which could pose significant risks to both individual patient care and to public health efforts. In response to these concerns, the FDA convened an advisory panel in June 2013 to discuss options to improve the regulation of the performance of RIDTs. A proposed order was published on 22 May 2014, and the final order published on 12 January 2017, reclassifying RIDTs from class I to class II medical devices, with additional requirements to comply with four new special controls. This reclassification is a landmark achievement in the regulation of diagnostic devices for infectious diseases and has important consequences for the future of diagnostic influenza testing with commercial tests, warranting the prompt attention of clinical laboratories, health care systems, and health care providers.