Why the SARS-CoV-2 antibody test results may be misleading: insights from a longitudinal analysis of COVID-19

To estimate the effectiveness of vaccines in development, a robust mechanism is required to understand immunity, risks of reinfection and measure the immune response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and how this may change over time. This study is a longitudinal analysis of COVID-19 infection rates using PCR, membrane immunoassay and chemiluminescent microparticle immunoassay (CMIA) diagnostic tests. Our data confirm that antibody levels wane in the three months after symptom onset. Comparison of the three methods used suggests that quantitative CMIA testing may exaggerate numbers of COVID-19 negative individuals.