Performance of Elecsys Anti-SARS CoV-2 (Roche) and VIDAS Anti-SARS CoV-2 (Biomérieux) for SARS-CoV-2 nucleocapsid and spike protein antibody detection

Abstract

IntroductionSevere acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the novel viral pathogen that causes coronavirus disease 2019 (COVID-19) in humans, has spread worldwide since its identification in late 2019. The pandemic produced an accelerated development of new serological techniques for diagnosis.MethodsWe evaluated two commercial assays for serological diagnosis of SARS-CoV-2 infection, approved by the Administración Nacional de Medicamentos, Alimenos y Tecnología Médica (ANMAT) in Argentina: Elecsys Anti-SARS-CoV-2; Roche for nucleocapsid total antibody detection, and VIDAS Anti-SARSCoV-2 bioMérieux for spike protein IgG antibody detection. Sensitivity was assessed using a panel of 92 plasma samples from recovered COVID-19 patients who were positive for RT-PCR and positive for neutralizing antibodies by plaque reduction neutralization test (PRNT) and/or positive for IgG antibodies by indirect immunofluorescence assay (IFA). Specificity was determined studying 71 plasma samples collected during year 2018 prior to the COVID-19 pandemic. Assays were evaluated as stand-alone tests.ResultsSensitivity was 97.8% and 98.9% for the Roche and bioMérieux assays, respectively, specificity:98.5% (Roche) and 97.1% (bioMérieux), positive predictive value (PPV): 98.9% (Roche) and 97.8%(bioMérieux), and negative predictive value: (NPV) 97.2% (Roche) and 98.5% (bioMérieux).Additionally, Cohen?s kappa coefficient demonstrated high concordance (k=0.950) betweenRoche and bioMérieux.DiscussionIn conclusion, our results evidenced a very good performance for the nucleocapsid antibody assay (Roche) and the spike protein antibody assay (bioMérieux), thus both platforms are equallyadequate for indirect diagnosis of SARS-CoV-2 infection through total antibodies and IgG antibody detection, respectively.