Accurate point-of-care serology tests for COVID-19

Area of Science:

• Infectious Diseases
• Immunology
• Point-of-Care Diagnostics

Background:

• Screening for prior SARS-CoV-2 infection and vaccine response is crucial with vaccine availability.
• Point-of-care (POC) testing offers a feasible approach for antibody detection.

Purpose of the Study:

• To evaluate the feasibility of POC antibody testing for identifying prior COVID-19 infection.
• To compare POC antibody assay performance with established immunoassays.

Main Methods:

• Prospective screening of at-risk individuals using lateral flow antibody assays on finger-stick blood.
• Comparison of POC results with serum-based CLIA nucleocapsid antibody immunoassay.
• Evaluation of variables: antibody class, time since PCR, and assay antigen.

Main Results:

• 512 subjects were enrolled; 104 had a history of COVID-19 and positive PCR.
• POC antibody tests showed high correlation with immunoassay (93-97% sensitivity).
• Serum testing did not enhance sensitivity or specificity compared to POC finger-stick blood.

Conclusions:

• POC finger-stick COVID-19 antibody testing effectively identifies antibodies from prior SARS-CoV-2 infections.
• High-complexity serum immunoassays offered no improvement over POC testing.
• POC antibody testing is a valuable tool for screening prior infections and assessing vaccine response.