Fig. 3.

Longitudinal anti-SARS-CoV-2 nucleocapsid antibody levels. The signal/noise (S/N) ratios of plasma antibody binding to the SARS-CoV-2 nucleocapsid (N) protein were determined for each of the 4 study groups. The S/N ratios for the non-hospitalised COVID-19 (a, blue, n = 89) and hospitalised COVID-19 (b, n = 50) groups were determined by the average binding of 5 unexposed healthy controls, with a S/N ratio over 1.1 determining positivity (dotted line). Reinfection was defined as a 2-fold S/N increase compared to the time point prior. The S/N ratio for the mRNA–mRNA (c, green, n = 96) and vector-mRNA (d, purple, n = 16) groups was determined by comparing the binding of each time point to the pre-vaccination time point. A S/N ratio above 3.0 was determined as positive (dotted line). Those highlighted in grey show individuals that did not get reinfected in the non-hospitalised COVID-19 and hospitalised COVID-19 groups and individuals that did not get infected in the mRNA–mRNA and vector-mRNA groups. Those in colour indicate individuals that became reinfected or infected.