Table 3.

Comparative epidemiologic outcomes with the bivalent vaccine coverage from Table 1 compared to the baseline coverage of a monovalent vaccine.

	Cross immunity 90%		Cross immunity 70%		Cross immunity 50%
Coverage for bivalent vaccine relative to baseline	% epidemics with lower cumulative incidence than baseline	Average epidemic size compared to baseline (95% CI)	% epidemics with lower cumulative incidence than baseline	Average epidemic size compared to baseline (95% CI)	% epidemics with lower cumulative incidence than baseline	Average epidemic size compared to baseline (95% CI)
Uniform coverage	100%	−100% (−100%,−100%)	100%	−100% (−100%,−100%)	100%	−100% (−100%,−100%)
50% increase	100%	−87% (−99.9%, −51.6%)	100%	−87.1% (−99.9%, −31.7%)	100%	−87.5% (−99.9%, −60.3%)
25% increase	100%	−63.5% (−99.7%, −26.6%)	100%	−63% (−99.7%, −31.7%)	100%	−62.9% (−99.7%, −36.7%)
10% increase	100%	−51.4% (−97.2%, −11.4%)	100%	−49.8% (−97.1%, −15.6%)	100%	−48.7% (−97.1%, −22.1%)
Baseline level	96.6%	−43.7% (−82.4%, 0.1%)	100%	−41.3% (−81.9%, −3.3%)	100%	−39.9% (−80.6%, −9.5%)
10% reduction	89.7%	−36.6% (−67.4%, 12.2%)	94.4%	−33.8% (−65.7%, 8%)	97%	−31.1% (−63.5%, 2.1%)
25% reduction	81.6%	−26.1% (−50%, 31.5%)	85.1%	−22.5% (−47.5%, 24.9%)	90%	−17.9% (−43.2%, 18.6%)
40% reduction	70%	−16% (−35%, 53%)	68.4%	−10.8% (−30.4%, 42.8%)	59.8%	−3.3% (−25.5%, 37%)