In Vitro Diagnostics for COVID-19: State-of-the-Art, Future Directions and Role in Pandemic Response

There have been tremendous advances in in vitro diagnostics (IVD) for coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Although the confirmatory clinical diagnosis is made by real-time reverse transcriptase polymerase chain reaction (RT-PCR), lateral flow immunoassay (LFIA) based viral antigen (Ag) detection is used for mass population screening at point-of-care (POC) settings. The rapid RT-PCR tests (such as from Cepheid and Bosch) have an assay duration of less than 40 min, while most rapid Ag tests (such as Abbott's BinaxNOW(TM) COVID-19 Ag card) have an assay duration of about 15 min. Of interest is the POC molecular test (ID NOW(TM)) from Abbott that takes less than13 min. Similarly, many immunoassays (IAs), i.e., automated chemiluminescent IA (CLIA), manual ELISA, and LFIA, have been developed to detect immunoglobulin G (IgG), immunoglobulin M (IgM), and immunoglobulin A (IgA) produced in subjects after SARS-CoV-2 infection. Many IVD tests have been approved by the United States Food and Drug Administration (FDA) under emergency use authorization (EUA), and almost all IVD tests are Conformité Européenne (CE) certified.