Performance of and Severe Acute Respiratory Syndrome Coronavirus 2 Diagnostics Based on Symptom Onset and Close Contact Exposure: An Analysis From the Test Us at Home Prospective Cohort Study

Carly Herbert; Biqi Wang; Honghuang Lin; Yi Yan; Nathaniel Hafer; Caitlin Pretz; Pamela Stamegna; Colton Wright; Thejas Suvarna; Emma Harman; Summer Schrader; Chris Nowak; Vik Kheterpal; Elizabeth Orvek; Steven Wong; Adrian Zai; Bruce Barton; Ben S Gerber; Stephenie C Lemon; Andreas Filippaios; Laura Gibson; Sharone Greene; Andres Colubri; Chad Achenbach; Robert Murphy; William Heetderks; Yukari C Manabe; Laurel O'Connor; Nisha Fahey; Katherine Luzuriaga; John Broach; Kristian Roth; David D McManus; Apurv Soni

doi:10.1093/ofid/ofae304

Performance of and Severe Acute Respiratory Syndrome Coronavirus 2 Diagnostics Based on Symptom Onset and Close Contact Exposure: An Analysis From the Test Us at Home Prospective Cohort Study

Open Forum Infect Dis. 2024 May 31;11(6):ofae304. doi: 10.1093/ofid/ofae304. eCollection 2024 Jun.

Authors

Carly Herbert^{1

2}, Biqi Wang^{1

3}, Honghuang Lin^{1

3}, Yi Yan⁴, Nathaniel Hafer^{2

5}, Caitlin Pretz¹, Pamela Stamegna¹, Colton Wright¹, Thejas Suvarna⁶, Emma Harman⁶, Summer Schrader⁶, Chris Nowak⁶, Vik Kheterpal⁶, Elizabeth Orvek⁷, Steven Wong⁷, Adrian Zai⁷, Bruce Barton⁷, Ben S Gerber⁷, Stephenie C Lemon⁷, Andreas Filippaios¹, Laura Gibson⁸, Sharone Greene⁸, Andres Colubri⁹, Chad Achenbach¹⁰, Robert Murphy¹⁰, William Heetderks¹¹, Yukari C Manabe¹², Laurel O'Connor¹³, Nisha Fahey^{1

7

14}, Katherine Luzuriaga^{2

5}, John Broach^{2

13}, Kristian Roth⁴, David D McManus^{1

3

15}, Apurv Soni^{1

3

7}

Affiliations

¹ Program in Digital Medicine, Department of Medicine, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA.
² University of Massachusetts Center for Clinical and Translational Science, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA.
³ Division of Health System Science, Department of Medicine, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA.
⁴ Division of Microbiology, OHT7 Office of Product Evaluation and Quality, Center for Devices and Radiological Health, US Food and Drug Administration, Silver Spring, Maryland, USA.
⁵ Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA.
⁶ CareEvolution, Ann Arbor, Michigan, USA.
⁷ Department of Population and Quantitative Health Sciences, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA.
⁸ Division of Infectious Disease, Department of Medicine, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA.
⁹ Department of Microbiology and Physiological Systems, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA.
¹⁰ Division of Infectious Disease, Department of Medicine, Havey Institute for Global Health, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA.
¹¹ National Institute of Biomedical Imaging and Bioengineering, NIH, via contract with Kelly Services, Bethesda, Maryland, USA.
¹² Division of Infectious Disease, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
¹³ Department of Emergency Medicine, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA.
¹⁴ Department of Pediatrics, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA.
¹⁵ Division of Cardiology, Department of Medicine, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA.

Abstract

Background: Understanding changes in diagnostic performance after symptom onset and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) exposure within different populations is crucial to guide the use of diagnostics for SARS-CoV-2.

Methods: The Test Us at Home study was a longitudinal cohort study that enrolled individuals across the United States between October 2021 and February 2022. Participants performed paired antigen-detection rapid diagnostic tests (Ag-RDTs) and reverse-transcriptase polymerase chain reaction (RT-PCR) tests at home every 48 hours for 15 days and self-reported symptoms and known coronavirus disease 2019 exposures immediately before testing. The percent positivity for Ag-RDTs and RT-PCR tests was calculated each day after symptom onset and exposure and stratified by vaccination status, variant, age category, and sex.

Results: The highest percent positivity occurred 2 days after symptom onset (RT-PCR, 91.2%; Ag-RDT, 71.1%) and 6 days after exposure (RT-PCR, 91.8%; Ag-RDT, 86.2%). RT-PCR and Ag-RDT performance did not differ by vaccination status, variant, age category, or sex. The percent positivity for Ag-RDTs was lower among exposed, asymptomatic than among symptomatic individuals (37.5% (95% confidence interval [CI], 13.7%-69.4%) vs 90.3% (75.1%-96.7%). Cumulatively, Ag-RDTs detected 84.9% (95% CI, 78.2%-89.8%) of infections within 4 days of symptom onset. For exposed participants, Ag-RDTs detected 94.0% (95% CI, 86.7%-97.4%) of RT-PCR-confirmed infections within 6 days of exposure.

Conclusions: The percent positivity for Ag-RDTs and RT-PCR tests was highest 2 days after symptom onset and 6 days after exposure, and performance increased with serial testing. The percent positivity of Ag-RDTs was lowest among asymptomatic individuals but did not differ by sex, variant, vaccination status, or age category.

Keywords: COVID-19; RT-PCR; SARS-CoV-2; SARS-CoV-2 variant; rapid antigen test.

Abstract

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