Table 3.

Identified Optimal Global Allocation by Income Setting. The optimal allocated coverage is the fully vaccinated persons per population, and the value in parentheses represents the proportion of total global doses allocated to that income setting. The Default scenario represents the default vaccine assumptions in Table 1. We also present the sensitivity of the allocation to changes in the assumptions about vaccine efficacy, vaccine efficacy in the 65 + years age group, mode of action of the vaccine, NPIs at vaccine introduction, health system constraints, reduced infectiousness in children younger than 10 years, and life-years gained (LYG) as an optimisation measure. The within-setting results are shown in Figures S12–S19, and the public health impact for each scenario is in Table S5. The estimated proportion of the global population in each income setting is included for reference.

	Allocated coverage of the population (proportion of global doses allocated to income setting)
	HIC	UMIC	LMIC	LIC
Reference: Proportion of global population	15.9%	37.3%	38.1%	8.7%
Default scenario	27.1% (33.2%)	8.6% (27.9%)	9.8% (32.6%)	8.5% (6.2%)
Lower vaccine efficacy (70%)	32.7% (40.2%)	7.8% (25.3%)	8.5% (28.3%)	8.5% (6.2%)
Reduced vaccine efficacy (scaled by 50%) in 65 + years population	27.1% (33.2%)	11.5% (37.3%)	6.9% (23.2%)	8.5% (6.2%)
Vaccine efficacious against disease only	18.3% (22.5%)	7.8% (25.3%)	13.1% (43.7%)	11.6% (8.5%)
NPIs maintained at higher level following vaccine introduction (such that Rt2 = 1.5)	11.3% (13.9%)	11.5% (37.1%)	11.2% (37.5%)	15.6% (11.5%)
NPIs maintained at lower level following vaccine introduction (such that Rt2 = 2.5)	29.2% (35.8%)	7.8% (25.3%)	9.8% (32.6%)	8.5% (6.2%)
Health system constraints absent	27.1% (33.2%)	15% (48.7%)	4.5% (15.2%)	4% (3%)
Reduced infectiousness in children younger than 10 years	29.3% (35.9%)	7.8% (25.3%)	9.7% (32.5%)	8.5% (6.2%)
LYG as optimisation outcome measure	27.1% (33.2%)	1.7% (5.5%)	10.7% (35.8%)	34.7% (25.6%)