Comparison of one single-antigen assay and three multi-antigen SARS-CoV-2 IgG assays in Nigeria

Nnaemeka C Iriemenam; Fehintola A Ige; Stacie M Greby; Olumide O Okunoye; Mabel Uwandu; Maureen Aniedobe; Stephnie O Nwaiwu; Nwando Mba; Mary Okoli; Nwachukwu E William; Akipu Ehoche; Augustine Mpamugo; Andrew Mitchell; Kristen A Stafford; Andrew N Thomas; Temitope Olaleye; Oluwaseun O Akinmulero; Ndidi P Agala; Ado G Abubakar; Ajile Owens; Sarah E Gwyn; Eric Rogier; Venkatachalam Udhayakumar; Laura C Steinhardt; Diana L Martin; McPaul I Okoye; Rosemary Audu

doi:10.1016/j.jcvp.2023.100139

Comparison of one single-antigen assay and three multi-antigen SARS-CoV-2 IgG assays in Nigeria

J Clin Virol Plus. 2023 Feb;3(1):100139. doi: 10.1016/j.jcvp.2023.100139. Epub 2023 Jan 13.

Authors

Nnaemeka C Iriemenam¹, Fehintola A Ige², Stacie M Greby¹, Olumide O Okunoye¹, Mabel Uwandu², Maureen Aniedobe², Stephnie O Nwaiwu², Nwando Mba³, Mary Okoli³, Nwachukwu E William³, Akipu Ehoche⁴, Augustine Mpamugo⁴, Andrew Mitchell⁵, Kristen A Stafford⁵, Andrew N Thomas⁶, Temitope Olaleye⁶, Oluwaseun O Akinmulero⁶, Ndidi P Agala⁶, Ado G Abubakar⁶, Ajile Owens⁷, Sarah E Gwyn⁷, Eric Rogier⁷, Venkatachalam Udhayakumar⁷, Laura C Steinhardt⁷, Diana L Martin⁷, McPaul I Okoye¹, Rosemary Audu²

Affiliations

¹ Division of Global HIV and TB, Center for Global Health, Centers for Disease Control and Prevention, Abuja, Nigeria.
² Center for Human Virology and Genomics, Microbiology Department, Nigerian Institute of Medical Research, Yaba, Lagos, Nigeria.
³ Nigeria Centre for Disease Control (NCDC), Gaduwa, FCT, Nigeria.
⁴ University of Maryland Center for International Health, Education, and Biosecurity (CIHEB), Maryland Global Initiatives Corporation (MGIC), FCT, Nigeria.
⁵ Center for International Health, Education, and Biosecurity, Institute of Human Virology, University of Maryland School of Medicine, Baltimore, USA.
⁶ International Research Center of Excellence, Institute of Human Virology, Abuja, Nigeria.
⁷ Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, GA, USA.

Abstract

Objectives: Determining an accurate estimate of SARS-CoV-2 seroprevalence has been challenging in African countries where malaria and other pathogens are endemic. We compared the performance of one single-antigen assay and three multi-antigen SARS-CoV-2 IgG assays in a Nigerian population endemic for malaria.

Methods: De-identified plasma specimens from SARS-CoV-2 RT-PCR positive, dried blood spot (DBS) SARS-CoV-2 RT-PCR positive, and pre-pandemic negatives were used to evaluate the performance of the four SARS-CoV-2 assays (Tetracore, SARS2MBA, RightSign, xMAP).

Results: Results showed higher sensitivity with the multi-antigen (81% (Tetracore), 96% (SARS2MBA), 85% (xMAP)) versus the single-antigen (RightSign (64%)) SARS-CoV-2 assay. The overall specificities were 98% (Tetracore), 100% (SARS2MBA and RightSign), and 99% (xMAP). When stratified based on <15 days to ≥15 days post-RT-PCR confirmation, the sensitivities increased from 75% to 88.2% for Tetracore; from 93% to 100% for the SARS2MBA; from 58% to 73% for RightSign; and from 83% to 88% for xMAP. With DBS, there was no positive increase after 15-28 days for the three assays (Tetracore, SARS2MBA, and xMAP).

Conclusion: Multi-antigen assays performed well in Nigeria, even with samples with known malaria reactivity, and might provide more accurate measures of COVID-19 seroprevalence and vaccine efficacy.

Keywords: Immunoassay; Nigeria; Pre-pandemic specimens; SARS-CoV-2; Sensitivity; Specificity.