A comparative review of immunoassays for COVID-19 detection

Area of Science:

• Virology
• Immunology
• Diagnostic Medicine

Background:

• Reverse transcription polymerase chain reaction (RT-PCR) is the gold standard for diagnosing COVID-19 but has limitations including cost, time, and potential false negatives.
• Serological tests detect antibodies against SARS-CoV-2, offering complementary diagnostic capabilities.
• These tests are crucial for RT-PCR negative patients, contact tracing, assessing immunity, and conducting seroepidemiological studies.

Purpose of the Study:

• To review and compare the diagnostic performance of major serological tests for SARS-CoV-2 detection.
• To evaluate enzyme-linked immunosorbent assays (ELISAs), chemiluminescent immunoassays (CLIAs), and lateral flow immunoassays (LFIAs).

Main Methods:

• A literature review was conducted on PubMed, Scopus, and Google Scholar databases.
• The review focused on comparative experiments of serological methods for COVID-19 detection between January 1, 2020, and December 31, 2020.
• Key serological methodologies including ELISAs, CLIAs, and LFIAs were analyzed.

Main Results:

• ELISA and CLIA methods demonstrated higher sensitivity compared to LFIA devices.
• Combining IgG/IgM titers can enhance the sensitivity of serology-based tests.
• Targeting the spike (S) antigen may lead to the development of more sensitive tests for detecting neutralization antibodies.

Conclusions:

• Serology testing can be integrated into diagnostic panels, particularly two weeks post-symptom onset.
• ELISA and CLIA offer superior sensitivity for SARS-CoV-2 antibody detection compared to LFIA.
• Future developments may focus on neutralization antibody detection for improved diagnostic accuracy.