The importance of combining serological testing with RT-PCR assays for efficient detection of COVID-19 and higher diagnostic accuracy

Sawsan S Alamri; Ahdab Alsaieedi; Yousef Khouqeer; Marwah Afeef; Samiyah Alharbi; Abdullah Algaissi; Maimonah Alghanmi; Tarfa Altorki; Ayat Zawawi; Mohamed A Alfaleh; Anwar M Hashem; Rowa Alhabbab

doi:10.7717/peerj.15024

The importance of combining serological testing with RT-PCR assays for efficient detection of COVID-19 and higher diagnostic accuracy

PeerJ. 2023 Apr 11:11:e15024. doi: 10.7717/peerj.15024. eCollection 2023.

Authors

Sawsan S Alamri¹, Ahdab Alsaieedi^{1

2}, Yousef Khouqeer³, Marwah Afeef⁴, Samiyah Alharbi⁵, Abdullah Algaissi^{6

7}, Maimonah Alghanmi^{1

2}, Tarfa Altorki^{1

2}, Ayat Zawawi^{1

2}, Mohamed A Alfaleh^{1

8}, Anwar M Hashem^{1

9}, Rowa Alhabbab^{1

2}

Affiliations

¹ Vaccines and Immunotherapy Unit, King Fahd Medical Research Centre, King Abdulaziz University, Jeddah, Saudi Arabia.
² Department of Medical Laboratory Sciences, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia.
³ College of Medicine, King Saud bin Abdulaziz University for Health Sciences, Jeddah, Saudi Arabia.
⁴ Study & Research Department, King Fahad General Hospital, Jeddah, Saudi Arabia.
⁵ Intensive Care Unit, King Fahad General Hospital, Jeddah, Saudi Arabia.
⁶ Department of Medical Laboratories Technology, College of Applied Medical Sciences, Jazan University, Jazan, Saudi Arabia.
⁷ Medical Research Centre, Jazan University, Jazan, Saudi Arabia.
⁸ Department of Pharmaceutics, Faculty of Pharmacy, King Abdulaziz University, Jeddah, Saudi Arabia.
⁹ Department of Medical Microbiology and Parasitology, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia.

Abstract

Misdiagnosing suspected COVID-19 individuals could largely contribute to the viruses transmission, therefore, making an accurate diagnosis of infected subjects vital in minimizing and containing the disease. Although RT-PCR is the standard method in detecting COVID-19, it is associated with some limitations, including possible false negative results. Therefore, serological testing has been suggested as a complement assay to RT-PCR to support the diagnosis of acute infections. In this study, 15 out of 639 unvaccinated healthcare workers (HCWs) were tested negative for COVID-19 by RT-PCR and were found seropositive for SARS-CoV-2 nucleocapsid protein-specific IgM and IgG antibodies. These participants underwent additional confirmatory RT-PCR and SARS-CoV-2 spike-specific ELISA tests. Of the 15 individuals, nine participants were found negative by second RT-PCR but seropositive for anti-spike IgM and IgG antibodies and neutralizing antibodies confirming their acute infection. At the time of collection, these nine individuals were in close contact with COVID-19-confirmed patients, with 77.7% reporting COVID-19-related symptoms. These results indicate that including serological tests in the current testing profile can provide better outcomes and help contain the spread of the virus by increasing diagnostic accuracy to prevent future outbreaks rapidly.

Keywords: COVID-19; Diagnostic; Healthcare worker; Infection; RT-PCR; SARS-CoV-2; Serology; Testing profile.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

COVID-19 Testing
COVID-19* / diagnosis
Humans
Immunoglobulin G / analysis
Immunoglobulin M / analysis
Reverse Transcriptase Polymerase Chain Reaction
SARS-CoV-2 / genetics

Substances

Immunoglobulin G
Immunoglobulin M

Grants and funding

This research work was funded by the Institutional Fund Projects from the Ministry of Education and King Abdulaziz University, Jeddah, Saudi Arabia, under grant no (IFPRC-160-290-2020). The funder played a role in the study design but had no role in data collection and analysis, decision to publish, or preparation of the manuscript.