Extended Data Fig. 6: Percentage (95% CI) anti-spike IgG positives by days after first vaccination in 2,067 participants receiving a single dose of BNT162b2 vaccine and with evidence of prior infection.

Results were divided into four age groups: 16–34, 35–54, 55–74 and >75 years. Exact binomial test was performed to obtain the 95% confidence intervals (shown as ‘error bars’). Numbers above the x-axis represent positive number/total number, and the percentage of positivity (%).