Between April 18 and June 17, 2020, 330 HCWs from five Madinah region-affiliated hospitals underwent a seroprevalence screening for anti-SARS-CoV-2 antibodies (immunoglobulin [Ig]M/IgA and IgG) using indirect ELISA testing. Result. Among the 330 samples, 80 (24.24%) were positive for SARS-CoV-2 IgM/IgA and/or IgG antibodies. the VITROS Immunodiagnostic Products Anti-SARS-CoV-2 IgG Quantitative Calibrator. Coronavirus Disease 2019 (COVID-19) 3. used) for the duration of the COVID-19 declaration COVID-19 can be treated with monoclonal antibodies against SARS-CoV-2, but emerging new variants might show resistance towards existing therapy. Here authors show that anti-SARS-CoV-2 spike human The test can provide information about how your body reacted to infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). SARS-CoV-2 is the name of the virus that causes coronavirus disease 2019 (COVID-19). It also can show how your body reacted to COVID-19 vaccines. Antibody testing also is known as serology testing. VITROS Immunodiagnostic Products Anti-SARS-CoV-2 IgG Reagent Pack Coronavirus Disease 2019 (COVID -19) The absolute sensitivity of the VITROS Immunodiagnostic Products Anti-SARS-CoV-2 IgG Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of coronavirus disease 2019 (COVID-19). RT-PCR detection of viral RNA represents the gold standard method for diagnosis of COVID-19. However, multiple diagnostic tests are needed for acute disease diagnosis and assessing immunity during the COVID-19 outbreak. Here, we developed in-house anti-RBD IgG and IgA (Refer to the official instruction manual for iFlash Immunoassay Analyzer for SARS-CoV-2 IgG and IgM). The cutoff of the CLIA quantitative antibody test was 10 AU/ml. S antigen, which may induce the production of neutralizing antibodies, as well as N antigen were targets for the antibody test. The IgG concentration of serum sample, expressed in international units per milliliter (BAU/ml), was calculated by extrapolation of the optical density at 450 nm (OD450) on a calibration curve built using serial dilutions of the WHO International Standard for anti-SARS-CoV-2 immunoglobulin. IgG antibodies against SARS-CoV-2 nucleocapsid protein j52Y.