Figure 4.

Pseudovirus neutralisation titres before and 28 days after boost vaccination by vaccine allocation and age group

Lines connect values from the same participant. Dotted line shows lower limit of the assay. Values below the limit were substituted with a titre of 20. Participants with antibody titres above the lower limit are considered seropositive. The midlines of the boxes show medians and the outer bounds of the boxes show IQRs. Error bars extend to the last data point within 1·5 × the IQR above or below the 75th or 25th percentile. See table 2 and appendix (pp 7–8) for summary statistics. Ad26=Ad.26.COV2-S. BNT=BNT162b2. ChAd=ChAdOx1 nCoV-19. CV=CoronaVac. IC₅₀=inhibitory concentration of serum achieving 50% neutralisation of virus (appendix pp 9–10).