Fig. 4: Estimation of the associations of baseline anti-N and BA.5 neutralizing antibody levels on infection risk in the subsampling population.

a, b, d, e, g, h The conditional effects of anti-N antibody level and BA.5 neutralizing antibody titers (NT) during the observation period on the absolute risk of both symptomatic and asymptomatic infection (a, b), symptomatic infection (d, e), and asymptomatic infection (g, h), respectively. Each predicted data point (blue dots), along with the median absolute risk (line) and 95% CredIs (ribbon), is shown. The overall risk of a control group with no vaccination or prior infection history in this cohort (0.184) (green solid line) and the 90% reduction of relative risk (i.e., 10% relative risk [10% RR]) (green dotted line) are shown. c, f, i The combined effect of anti-N antibody level and BA.5 NT during the observation period on the absolute risk of both symptomatic and asymptomatic infection (c), symptomatic infection (f), and asymptomatic infection (i), respectively. The logarithmic absolute risk of infection is indicated by the color bar. The white dotted and solid lines show the log₁₀ absolute risk decrease for every 0.5 and 1.0, respectively. Overall (a–c) and symptomatic infection (d–f); n = 340. Asymptomatic infection (g–i); n = 324.