Laboratory-Based SARS-CoV-2 Receptor Binding Domain Serologic Assays Perform with Equivalent Sensitivity and...

Area of Science:

• Virology
• Epidemiology
• Immunology

Background:

• Early SARS-CoV-2 pandemic response involved rapid development of diagnostic tests.
• Limited validated clinical samples impacted Emergency Use Authorization for some tests.
• Skilled nursing facilities were key sites for early serologic testing.

Approach:

• Evaluated six laboratory-based and two commercial assays using 186 serum samples from May 2020.
• Utilized serum neutralization titers and positive to negative ratio (P/N) analysis for cut-off determination.
• Compared serologic test performance with quantitative PCR (qPCR) outcomes.

Key Points:

• Laboratory-based receptor binding domain (RBD) binding assays demonstrated comparable or superior sensitivity and specificity.
• Seroconversion rates were determined and analyzed in relation to qPCR results.
• Batch effects were addressed using P/N analysis for reliable cut-off values.

Conclusions:

• Research laboratory assays provide reliable surveillance data for infectious disease outbreaks.
• These assays serve as valuable adjuncts to commercial testing during the initial stages of an epidemic.
• Findings support the integration of research lab capabilities into public health surveillance strategies.