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Dynamic Monitoring of Seroconversion using a Multianalyte Immunobead Assay for Covid-19
Published on: February 16, 2022
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Mapping a Pandemic: SARS-CoV-2 Seropositivity in the United States
Heather Kalish1, Carleen Klumpp-Thomas2, Sally Hunsberger3
1Trans-NIH Shared Resource on Biomedical Engineering and Physical Science, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD 20894.
Medrxiv : the Preprint Server for Health Sciences
|February 3, 2021
Summary
Undiagnosed SARS-CoV-2 infections were common in US adults during Spring/Summer 2020, with 4.6% seropositivity. This indicates 4.8 undiagnosed cases for every diagnosed COVID-19 case, highlighting significant undercounting of viral prevalence.
Area of Science:
- Epidemiology
- Infectious Diseases
- Public Health
Background:
- Asymptomatic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections and diagnostic delays obscured true viral prevalence.
- Accurate estimation of seroprevalence is crucial for understanding disease spread and impact.
Approach:
- Analyzed seropositivity in US adults without prior COVID-19 diagnosis using ELISA for anti-Spike and anti-RBD antibodies.
- Utilized quota sampling to ensure population representativeness (n=11,382) and weighted analysis for prevalence estimation.
- Collected demographic, geographic, socioeconomic, and medical data from participants.
Key Points:
- Detected a 4.6% undiagnosed SARS-CoV-2 seropositivity rate among US adults between May and July 2020.
- Observed significant regional variation, with higher rates in areas of early outbreaks.
- Identified higher undiagnosed seropositivity in younger adults (18-45), females, Black/African Americans, Hispanics, and urban residents.
Conclusions:
- Estimated 4.8 undiagnosed SARS-CoV-2 infections for every diagnosed case during the first wave.
- By mid-July 2020, an estimated 16.8 million undiagnosed COVID-19 cases existed in the US.
- Findings underscore the substantial burden of asymptomatic and undiagnosed SARS-CoV-2 infections.
