Importance of antigen detection for the screening of COVID-19

Abstract

Since the beginning of the COVID-19 pandemic, laboratories have been using nucleic acid amplification tests, such as real time reverse transcription polymerase chain reaction (rRT-PCR) assays, to detect SARS-CoV-2, the virus that causes the disease. In many countries, access to this form of testing has been challenging. A new technology for COVID-19 detection has become available that is much simpler and faster to perform that currently-recommended nucleic acid amplification tests (NAAT), like PCR. This method relies on direct detection of SARS-CoV-2 viral proteins in nasal swabs and other respiratory secretions using a lateral flow immunoassay (also called an RDT) that gives results in < 30 minutes. Though these antigen detection RDTs (Ag-RDTs) are substantially less sensitive than NAAT, they offer the possibility of rapid, inexpensive and early detection of the most infectious COVID cases in appropriate settings.