Table 1. Model parameters given with their descriptions, constrained ranges, and prior distributions.

Notation	Description	Constained range or definition	Prior distribution ‡
$R_0^p$	Basic reproduction number of the primarily infected population	0 − ∞	$R_0^p\sim \mathcal{N}(2.5,0.5)$
rc	Reduction in infectiousness due to being chronic	0%–100%	Fixed to a different value for each simulation.
$R_0^c$	Basic reproduction number of the chronically infected population	$R_0^c=R_0^p(1-r_c)$	Conditioned on $R_0^p$ and rc.
rL	Effect of lockdown in reducing infectiousness	0%–100%	rL ∼ β(1, 1)
mL	Slope of reduction in infectiousness due to lockdown	0.5–1.5	mL ∼ 0.5 + β(1, 1)
sL	Time lag of reduction in infectiousness due to lockdown	0 − ∞	sL ∼ exp(1/5)
rlock(t)	Time dependent effect of the lockdown on the transmission rate	Given by Eq 2	Conditioned on rL, rc, mL, and sL.
1/τ	Duration of the latent period	0 − ∞	τ ∼ exp(1/2.5)
1/γp	Duration of infection of Ip	0 − ∞	γp ∼ exp(1/2.5)
1/γc	Duration of infection of Ic	0.01-20 days	Fixed to a different value for each simulation.
βp	Transmission rate of Ip	Given by Eq 3	Conditioned on rlock(t), R0, and γp.
βc	Transmission rate of Ic	Given by Eq 4	Conditioned on rlock(t), R0, γc, and rc.
1/γH	Duration of hospital ward stay	0 − ∞	γH ∼ exp(1/12)
1/γICU	Duration of ICU stay	0 − ∞	γICU ∼ exp(1/12)
ϵH	Rate of direct H admission	0 − ∞	${ϵ}_H\sim \mathcal{N}(0.08,0.02)$
ϵH2I	Transfer rate from H to ICU	0 − ∞	${ϵ}_{H2I}\sim \mathcal{N}(0.4,0.08)$
ϵx	Death rate from ICU	0 − ∞	${ϵ}_x\sim \mathcal{N}(0.4,0.08)$
$r_d^p$	Diagnosis rate of Ip	0 − ∞	$r_d^p\sim \mathcal{N}(0.2,0.03)$
$r_d^c$	Diagnosis rate of Ic	0 − ∞	$r_d^c\sim \mathcal{N}(0.075,0.015)$
R0	Total basic reproduction number	$R_0=R_0^p+(1-{ϵ}_H)R_0^c$	Conditioned on $R_0^p$, $R_0^c$ and ϵH.
E(0)	Initial frequency of the exposed compartment	0%–100%	$r_d^c\sim \beta (1,{10}^3)$
S(0)	Initial frequency of the susceptible compartment	1 − E(0)*	Conditioned on E(0)
N	Population size	−	Fixed specific to the country used for fitting.

* All other compartments (I_p, I_c, H, ICU, R, and X) are assumed to be zero at t = 0, and the first case is assumed to be observed at t = 1.

^‡ $\mathcal{N}$, β, exp denotes the Normal, Beta, and Exponential distributions respectively.