Table 1 -.

List of modelling scenarios and key assumptions. Scenarios marked with an asterisk (*) are equivalent. Mobility scenarios are shown in Figure 3. Assumptions for waning scenarios are given in Table S4. Assumptions for vaccine effectiveness against different SARS-CoV-2 variants are given in Table S2. Assumptions for cross-protection against different SARS-CoV-2 variants given prior infection are given in Table S3.

Scenario	Result type	Assumptions
		Mobility	Waning	Booster uptake	Seasonality	Vaccine policy
Basecase*	-	6-month	Central	Actual	20%	5+ 80% uptake
No return	Behaviour	No change	Central	Actual	20%	5+ 80% uptake
6-month return*		6-month	Central	Actual	20%	5+ 80% uptake
3-month return		3-month	Central	Actual	20%	5+ 80% uptake
3-week return		3-week	Central	Actual	20%	5+ 80% uptake
No boosters	Boosters eligibility / uptake (relative to second dose levels)	6-month	Central	None	20%	5+ 80% uptake
50+ boosters		6-month	Central	95% in 50+ only	20%	5+ 80% uptake
Actual boosters*		6-month	Central	Age-specific measured uptake as of 14th April 2022†. Individuals aged 50 and above have at least 86.1% and at most 96.7% uptake. Individuals aged 15–49 have at least 40% and at most 80.9% uptake, relative to second dose levels of uptake.	20%	5+ 80% uptake
High uptake		6-month	Central	90% in <50s; 98% in 50+	20%	5+ 80% uptake
Central waning*	Waning	6-month	Central	Actual	20%	5+ 80% uptake
High waning		6-month	High	Actual	20%	5+ 80% uptake
Very high waning		6-month	Very high	Actual	20%	5+ 80% uptake
10%	Seasonality	6-month	Central	Actual	10%	5+ 80% uptake
20%*		6-month	Central	Actual	20%	5+ 80% uptake
30%		6-month	Central	Actual	30%	5+ 80% uptake
40%		6-month	Central	Actual	40%	5+ 80% uptake
5+, 80%*	Vaccine uptake for children	6-month	Central	Actual	20%	5+ 80% uptake
5+, 50%		6-month	Central	Actual	20%	5+ 50% uptake

^†The detailed age-specific probability of receiving a booster vaccine for this scenario is listed in Table S5B.