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

Abstract

Background As COVID-19 vaccines become available, screening individuals for prior COVID-19 infection and vaccine response in point-of-care (POC) settings has renewed interest. We prospectively screened at-risk individuals for SARS-CoV-2 spike and nucleocapsid protein antibodies in a POC setting to determine if it was a feasible method to identify antibody from prior infection. Methods Three EUA-approved lateral flow antibody assays were performed on POC finger-stick blood and compared with serum and a CLIA nucleocapsid antibody immunoassay. Variables including antibody class, time since PCR, and the assay antigen used were evaluated. Results 512 subjects enrolled, of which 104 had a COVID-19 history and positive PCR. Only three PCR-positive subjects required hospitalization, with one requiring mechanical ventilation. The POC results correlated well with the immunoassay (93–97% sensitivity) and using serum did not improve the sensitivity or specificity. Conclusions Finger-stick, POC COVID-19 antibody testing was highly effective in identifying antibody resulting from prior infections in mildly symptomatic subjects. Using high-complexity serum immunoassays did not improve the screening outcome. Almost all individuals with COVID-19 infection produced detectable antibodies to the virus. POC antibody testing is useful as a screen for prior COVID-19 infection, and should be useful in assessing vaccine response.

Qualitative assessment of anti‐SARS‐CoV‐2 spike protein immunogenicity (QUASI) after COVID‐19 vaccination in older people living with HIV

“…This Healgen lateral flow assay point‐of‐care test produces a binary result (positive or negative) for SARS‐COV‐2 anti‐spike antibody for both IgG and IgM. Its ability to serve as an accurate point‐of‐care serology test for COVID‐19 has been substantiated [ 10] . It has been tested predominantly among healthcare workers in a real‐world clinical setting, and when compared with a CLIA laboratory‐based serum immunoassay antibody test, it demonstrated 93.2% sensitivity and 94.9% specificity in one study [ 10] .…”

Clinical Application of the Novel Cell-Based Biosensor for the Ultra-Rapid Detection of the SARS-CoV-2 S1 Spike Protein Antigen: A Practical Approach

“…In practical terms, screening for viral antigens differentiates itself from antibody-targeting serology tests since it does not depend on host antibody accumulation to detectable levels in the second and third week of illness [5]. The interest in screening individuals for COVID-19 infection in point-of-care (POC) settings is concomitant with the wide vaccination against the virus [6]. Although nucleic acid-based tests are considered the golden standard for SARS-CoV-2, they are prone to false-negative or even contradictory results, especially before or at symptom onset [7][8][9].…”

Fabrication of a Lateral Flow Assay for Rapid In-Field Detection of COVID-19 Antibodies Using Additive Manufacturing Printing Technologies

“…Indeed, a cost-effective diagnostic tool would be beneficial for wide community screening. Rapid tests offer comparable outcomes to the laboratory-based tests and can be used when there is a need to identify people with immunity against the virus within a few minutes while having the advantages of being user-friendly, portable, and not requiring expensive instruments[ 10 ].…”