Test Us At Home

Background: The purpose of this study was to evaluate how well antigen rapid diagnostic tests (Ag-RDTs) detected SARS-CoV-2 at different points in the course of infection among symptomatic and asymptomatic people. The study also aimed to understand early detection performance in individuals who began the study without symptoms and with negative antigen and molecular test results.

Materials/Methods: Participants in this prospective cohort study were older than two years and were recruited nationwide through a smartphone app. At each testing encounter, participants self-collected one nasal swab and completed an at-home Ag-RDT. At least 15 minutes later, they self-collected a second nasal swab and shipped it to a central laboratory for RT-PCR testing. Both nasal swabs were collected seven times at 48-hour intervals across about 14 days. Participants then collected one additional nasal swab with a home Ag-RDT 48 hours after the final PCR collection. Each participant used one of the three Ag-RDTs with emergency use authorization. The study only included participants who were asymptomatic and negative by both antigen and molecular tests on their first day in the study.

Outcome/Impact: The study produced detailed evidence on how Ag-RDT performance changes over the early period of infection. The results informed real-world expectations for antigen testing among asymptomatic people and clarified detection windows for the three EUA Ag-RDTs tested. These findings supported public health guidance on repeated home testing and improved understanding of how to use Ag-RDTs for early identification of SARS-CoV-2 infection in community settings. Sequencing data from this study are available in the Sequence Read Archive (SRA) repository and can be accessed here: https://www.ncbi.nlm.nih.gov/bioproject/988487.