Estimated secondary attack rates without and with vaccination.

The vaccine is assumed to be 90% effective (VES = 0.9) in preventing infection and moderately effective reducing infectiousness (VEI = 0.5). Shown are inferred secondary attack rates (SARs) for various household compositions. Estimates are represented by posterior medians and 2.5% and 97.5% posterior quantiles. See Table 5 for details, and results without vaccination and with vaccination with a vaccine that does not reduce infectiousness.