Optimizing SARS-CoV-2 Immunoassays for Specificity in Dengue-Co-Endemic Areas

Nihad Adnan; Md Ahsanul Haq; Taslima Akter Tisha; Shahad Saif Khandker; Mohd Raeed Jamiruddin; Sm Shafiul Alam Sajal; Salma Akter; Md Firoz Ahmed; Rubhana Raqib; Mohib Ullah Khondoker; Nafisa Azmuda; Mainul Haque

doi:10.7759/cureus.47683

Optimizing SARS-CoV-2 Immunoassays for Specificity in Dengue-Co-Endemic Areas

Cureus. 2023 Oct 25;15(10):e47683. doi: 10.7759/cureus.47683. eCollection 2023 Oct.

Affiliations

¹ Microbiology, Jahangirnagar University, Dhaka, BGD.
² Bio-Statistics, Infectious Diseases Division, International Centre for Diarrhoeal Disease Research, Bangladesh (icddr, b), Dhaka, BGD.
³ Biochemistry and Molecular Biology, Gonoshasthaya Samaj Vittik Medical College, Dhaka, BGD.
⁴ Pharmacy, Bangladesh Rural Advancement Committee (BRAC) University, Dhaka, BGD.
⁵ Immunology, Nutrition, and Toxicology Laboratory, Infectious Diseases Division, International Centre for Diarrhoeal Disease Research, Bangladesh (icddr, b), Dhaka, BGD.
⁶ Community Medicine, Gonoshasthaya Samaj Vittik Medical College, Dhaka, BGD.
⁷ Department of Research, School of Dentistry, Karnavati Scientific Research Center (KSRC) Karnavati University, Gandhinagar, IND.
⁸ Pharmacology and Therapeutics, National Defence University of Malaysia, Kuala Lumpur, MYS.

Abstract

Introduction The overlap in clinical presentation between COVID-19 and dengue poses challenges for diagnosis in co-endemic regions. Furthermore, there have been reports of antibody cross-reactivity between SARS-CoV-2 and dengue. Our research aims to evaluate SARS-CoV-2 antigens for serological testing while reducing the possibility of cross-reactivity with anti-dengue antibodies. Method Two hundred and ten serum samples were collected from 179 patients and divided into four panels. Panels 1 and 2 consisted of COVID-19-negative healthy donors (n=81) and pre-pandemic dengue patients (n=50), respectively. Alternatively, Panel 3 (n=19) was composed of reverse transcription-quantitative polymerase chain reaction (RT-qPCR)-positive samples collected within two weeks of COVID-19 symptom onset, while Panel 4 (n=60) was composed of positive samples collected after two weeks of symptom onset. Previously developed and characterized in-house SARS-CoV-2 spike-1 (S1), receptor binding domain (RBD), and nucleocapsid (N) immunoglobin G (IgG)-enzyme-linked immunosorbent assay (ELISA) assays were used for the study. Results Six dengue-positive sera cross-reacted with the RBD of SARS-CoV-2. However, only one dengue-positive sera cross-reacted with the S1 and N proteins of SARS-CoV-2. Co-immobilization of S1 and RBD in different ratios revealed an 80:20 (S1:RBD) ratio as optimal for achieving an overall 96.2% sensitivity with the least cross-reaction to anti-dengue antibodies. Conclusion Our findings indicated that SARS-CoV-2 RBD-based immunoassays present more cross-reactivity with anti-dengue antibodies than S1 and N proteins. Furthermore, co-immobilization of S1 and RBD reduces the cross-reactivity with anti-dengue antibodies compared to RBD, thereby increasing the immunoassay specificity without affecting overall sensitivity for the dengue-endemic areas.

Keywords: covid-19; cross-reactivity; dengue; dengue co-endemic areas; elisa; immunoassay; maximize; precision; sensitivity specificity; spike protein.

Grants and funding

The project was conducted with grant support (code: 1260101-120005400) from the Ministry of Science and Technology, Bangladesh Secretariat, 1000 Abdul Gani Rd., Dhaka, Bangladesh.