Upon infection with SARS-CoV-2, the host mounts an immune response against the virus, including the production of antibodies against various viral proteins, such as the Spike protein, which mediates virus binding to a receptor on cells to initiate infection. Antibodies against the receptor-binding domain of Spike (Spike-RBD) as tested in the NanoSpot.ai SARS-CoV-2 antibody test, correlate particularly well with a strong neutralizing response. Accordingly, all current vaccines are based on the Spike protein. Measuring antibodies directed against the Spike protein, obtained either through natural infection or upon vaccination, can therefore provide a measure for immunity against SARS-CoV-2. While the COVID-19 antibody test cannot find out whether you are currently infected, the antibody test will provide information if your previously had the virus or a COVID-19 vaccine and how your body responded to a Covid-19 infection or the vaccine. In general, the higher the antibody levels, the higher the level of protection.