marofib
Forumer storico
Figure 2 shows the Cox modelled effects of time since vaccination on the vaccine effectiveness. From the first to the ninth month the vaccine effectiveness against the infection decreased progressively from 78% to 10%, with a relative reduction of 87·0% (95% CI 75·8–93·0). From the first to the seventh month the vaccine effectiveness against severe illness decreased from 86% to 49%, with a relative reduction of 43·5% (95% CI 24·5–57·7). Because the models did not reach convergence, estimates beyond the seventh month were not obtained. Further details on the effect of selected covariates on the infection and severe illness hazard ratios are reported in the appendix (pp 12–13).