Table 1.

Epidemiological parameters.

Parameters		Values	Source	Sensitivity analysis
The proportion of people who got vaccinated 2 doses before epidemic in Guangzhou	$V$	13.64%	The People's Government of Guangzhou Municipality17
The total population in Guangzhou	$N$	18.68 million	National Bureau of Statistics18
Basic reproduction number	R0	3.2	Zhang, M. et al16, sensitivity analyses	3.2, 4.0, 5.0, 6.0 (Supplementary Figure S1)
Quarantine/isolation effect	$q$	0–100%	1/tc
Vaccine efficacy for preventing infection by Delta variant	$e$	59%	Xiao-Ning Li. et al19
Incubation period	$L$	4.4 days	Zhang, M. et al16. Duration from exposure to onset, sensitivity analyses	2, 3, 4.4, 5, 6 (Supplementary Figure S2)
The rate of transmission via contact with active Infections	$\beta$	0.0082	Total number of infections /total number of close contacts via infections
Recovery period	D	14 days	Rees, E. M. et al20	10, 12, 14, 16, 18 days (Supplementary Figure S3)
Average contact rate	C(t)	Varied for each phase (0–31)		0-31 person × 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 100%, 110%, 120%, 130% (Supplementary Figure S4)
Time from onset of infectiousness to quarantine/isolation	tc	Quarantine: (-4–1 days) Isolation: (0–3 days)		− 3, − 2, − 1, 0, 1, 2, 3 days (Supplementary Figure S5)
Time of response to the whole control measure (phase I–IV) in Guangzhou	T	[3, 5, 7]		− 3, − 2, − 1, 0, 3, 5, 7 (Supplementary Figure S6)