Performance of Rapid Antigen Tests to Detect Symptomatic and Asymptomatic SARS-CoV-2 Infection : A Prospective Cohort Study

Abstract

<p xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" class="first" id="d8299052e770">This prospective study evaluated the performance of rapid antigen tests for detection of SARS-CoV-2 among symptomatic and asymptomatic participants. Participants who were asymptomatic and negative for SARS-CoV-2 on study day 1 completed rapid antigen tests and RT-PCR testing for SARS-CoV-2 every 48 hours for 15 days. </p><div xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" class="fig panel" id="fva1-M230385"> <a class="named-anchor" id="fva1-M230385"> <!-- named anchor --> </a> <div class="figure-container so-text-align-c"> <img alt="" class="figure" src="/document_file/96ade31c-ed83-4189-8ec2-4a6ded166e27/PubMedCentral/image/aim-olf-M230385-AIME202307180-M230385_visual-abstract"/> </div> <div class="panel-content"> <div class="label">Visual Abstract.</div> <div class="caption" id="d8299052e776"> <strong> <span class="fig-title">Performance of Rapid Antigen Tests to Detect Symptomatic and Asymptomatic SARS-CoV-2 Infection </span> </strong> <p id="d8299052e779">This prospective study evaluated the performance of rapid antigen tests for detection of SARS-CoV-2 among symptomatic and asymptomatic participants. Participants who were asymptomatic and negative for SARS-CoV-2 on study day 1 completed rapid antigen tests and RT-PCR testing for SARS-CoV-2 every 48 hours for 15 days. </p> </div> </div> </div><div xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" class="section"> <a class="named-anchor" id="d8299052e783"> <!-- named anchor --> </a> <h5 class="section-title" id="d8299052e784">Background:</h5> <p id="d8299052e786">The performance of rapid antigen tests (Ag-RDTs) for screening asymptomatic and symptomatic persons for SARS-CoV-2 is not well established. </p> </div><div xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" class="section"> <a class="named-anchor" id="d8299052e788"> <!-- named anchor --> </a> <h5 class="section-title" id="d8299052e789">Objective:</h5> <p id="d8299052e791">To evaluate the performance of Ag-RDTs for detection of SARS-CoV-2 among symptomatic and asymptomatic participants. </p> </div><div xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" class="section"> <a class="named-anchor" id="d8299052e793"> <!-- named anchor --> </a> <h5 class="section-title" id="d8299052e794">Design:</h5> <p id="d8299052e796">This prospective cohort study enrolled participants between October 2021 and January 2022. Participants completed Ag-RDTs and reverse transcriptase polymerase chain reaction (RT-PCR) testing for SARS-CoV-2 every 48 hours for 15 days. </p> </div><div xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" class="section"> <a class="named-anchor" id="d8299052e798"> <!-- named anchor --> </a> <h5 class="section-title" id="d8299052e799">Setting:</h5> <p id="d8299052e801">Participants were enrolled digitally throughout the mainland United States. They self-collected anterior nasal swabs for Ag-RDTs and RT-PCR testing. Nasal swabs for RT-PCR were shipped to a central laboratory, whereas Ag-RDTs were done at home. </p> </div><div xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" class="section"> <a class="named-anchor" id="d8299052e803"> <!-- named anchor --> </a> <h5 class="section-title" id="d8299052e804">Participants:</h5> <p id="d8299052e806">Of 7361 participants in the study, 5353 who were asymptomatic and negative for SARS-CoV-2 on study day 1 were eligible. In total, 154 participants had at least 1 positive RT-PCR result. </p> </div><div xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" class="section"> <a class="named-anchor" id="d8299052e808"> <!-- named anchor --> </a> <h5 class="section-title" id="d8299052e809">Measurements:</h5> <p id="d8299052e811">The sensitivity of Ag-RDTs was measured on the basis of testing once (same-day), twice (after 48 hours), and thrice (after a total of 96 hours). The analysis was repeated for different days past index PCR positivity (DPIPPs) to approximate real-world scenarios where testing initiation may not always coincide with DPIPP 0. Results were stratified by symptom status. </p> </div><div xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" class="section"> <a class="named-anchor" id="d8299052e813"> <!-- named anchor --> </a> <h5 class="section-title" id="d8299052e814">Results:</h5> <p id="d8299052e816">Among 154 participants who tested positive for SARS-CoV-2, 97 were asymptomatic and 57 had symptoms at infection onset. Serial testing with Ag-RDTs twice 48 hours apart resulted in an aggregated sensitivity of 93.4% (95% CI, 90.4% to 95.9%) among symptomatic participants on DPIPPs 0 to 6. When singleton positive results were excluded, the aggregated sensitivity on DPIPPs 0 to 6 for 2-time serial testing among asymptomatic participants was lower at 62.7% (CI, 57.0% to 70.5%), but it improved to 79.0% (CI, 70.1% to 87.4%) with testing 3 times at 48-hour intervals. </p> </div><div xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" class="section"> <a class="named-anchor" id="d8299052e818"> <!-- named anchor --> </a> <h5 class="section-title" id="d8299052e819">Limitation:</h5> <p id="d8299052e821">Participants tested every 48 hours; therefore, these data cannot support conclusions about serial testing intervals shorter than 48 hours. </p> </div><div xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" class="section"> <a class="named-anchor" id="d8299052e823"> <!-- named anchor --> </a> <h5 class="section-title" id="d8299052e824">Conclusion:</h5> <p id="d8299052e826">The performance of Ag-RDTs was optimized when asymptomatic participants tested 3 times at 48-hour intervals and when symptomatic participants tested 2 times separated by 48 hours. </p> </div><div xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" class="section"> <a class="named-anchor" id="d8299052e828"> <!-- named anchor --> </a> <h5 class="section-title" id="d8299052e829">Primary Funding Source:</h5> <p id="d8299052e831">National Institutes of Health RADx Tech program.</p> </div>