Table 2. Input parameters.

Dates for the first and N^th observed cases correspond to the dates in the data set. A case in the context of the Alpha variant in the UK is defined as a sequenced sample, whereas a case in the context of COVID-19 in Wuhan is defined as a confirmed, symptomatic case. The total numbers of observed cases correspond to the size of the data set used to inform the model. The key epidemiological parameters are obtained from available literature (references in brackets, next to the parameter values).

Parameter	Symbol	Alpha	SARS-CoV-2
Total number of observed cases	N	406	3072
Date of first reported case	$d_1^{\text{obs}}$	Sep 20, 2020	Dec 10, 2019
Date of Nth observed case	$d_{K^{\prime }}^{\text{obs}}$	Nov 11, 2020	Jan 19, 2020
Expected number of secondary cases	R	1.90 [12]	2.50 [37]
	κ	0.57 [11]	0.10 [38]
Secondary infection generation time	ω t	0.83 [39]†	0.83 [39]
	θ t	6.60 [39]†	6.60 [39]
Probability of case detection	p detect	0.01 [40, 41]†	0.15 [37]
Time from infection to detection	ω τ	0.58 [11]	1.04 [42]
	θ τ	12.0 [11]	6.25 [42]
Tolerance on the daily number of cases*	${\delta }_{\text{tol}}^Y$	0.3	0.3

* Used to select the simulations that resemble the observed data; cf. the Methods section.

^† We use the parameters from the studies cited in [11].