A COVID-19 antibody test needs to be accurate so that antibodies to other viruses like the common cold cannot be mistaken for antibodies to COVID-19. Coronaviruses share structural similarities and are made up of 4 key proteins. By capturing the S1 antigen, the most unique of these 4 proteins, Ortho minimizes the risk of false positives or identifying someone as having an immune response to the virus when they do not.
