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

• Published in: Curēus (Palo Alto, CA) CA), 2023-10, Vol.15 (10), p.e47683-e47683
• Main Authors: Adnan, Nihad, Haq, Md Ahsanul, Tisha, Taslima Akter, Khandker, Shahad Saif, Jamiruddin, Mohd. Raeed, Sajal, SM Shafiul Alam, Akter, Salma, Ahmed, Md Firoz, Raqib, Rubhana, Khondoker, Mohib Ullah, Azmuda, Nafisa, Haque, Mainul
• Format: Article
• Language: English
• Subjects: Accuracy; Agreements; Antigens; Confidence intervals; COVID-19 vaccines; Dengue fever; Disease transmission; Enzymes; Healthcare Technology; Immunoassay; Infectious Disease; Pandemics; Polymerase chain reaction; Proteins; Quality Improvement; Research ethics; Severe acute respiratory syndrome coronavirus 2; Statistical analysis
• ISSN: 2168-8184; 2168-8184
• DOI: 10.7759/cureus.47683

IntroductionThe 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.MethodTwo 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.ResultsSix 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.ConclusionOur 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.