Table 2. Model parameters and priors/values.

Parameter	Description	Prior/value	Source/Notes
${\displaystyle \overline{\beta }}$	Overall contact rate (1/days)	Estimated: Uniform(0,100)
${\displaystyle c^{\left(cc\right)}}$	Relative initial contact rate between crew/crew	Fixed: 1
${\displaystyle c^{\left(pp\right)}}$	Relative initial contact rate between passengers/passengers	Estimated: Uniform(0,100)
${\displaystyle c^{\left(pc\right)}}$	Relative initial contact rate between passengers/crew	Fixed relative to ${\displaystyle c^{(pp)}}$
X	Ratio: ${\displaystyle \frac{c^{(pc)}}{c^{(pp)}}}$	Fixed: 0.1	Assumed. Varied in sensitivity analyses
b1	Percentage reduction in all initial contact rates (%)	Estimated: Uniform(0,100)
b2	Rate of change of all contact rates (1/days)	Fixed: 10	Assumed. Transitions completed over approximately one day
${\displaystyle {\tau }^{(pp)},{\tau }^{(pc)}}$	Time of transition for contacts between passengers/passengers and passengers/crew (days)	Estimated: Uniform(0,32)	Assumed to be equal to each other
${\displaystyle {\tau }^{(cc)}}$	Time of transition for contacts between crew/crew (days)	Estimated: Uniform(0,32)
${\displaystyle {\theta }_p}$	Relative infectiousness of presymptomatic state	Estimated: Uniform(0,1)	Relative to symptomatic state
${\displaystyle {\theta }_a}$	Relative infectiousness of asymptomatic state	Estimated: Uniform(0,1)	Relative to symptomatic state
${\displaystyle \chi }$	Proportion of infections that proceed to asymptomatic state	Estimated: Uniform(0,1)
${\displaystyle \frac{1}{v}}$	Latent period (days)	Fixed: 4.3	Derived from Backer et al., 2020
${\displaystyle \frac{1}{{\gamma }_a}}$	Mean duration in asymptomatic state (days)	Fixed: 5.0	Assumed. Sum of mean durations in presymptomatic and symptomatic states. Varied in sensitivity analyses.
${\displaystyle \frac{1}{{\gamma }_p}}$	Mean duration in presymptomatic state (days)	Fixed: 2.1	Derived from Backer et al., 2020
${\displaystyle \frac{1}{{\gamma }_s}}$	Mean duration in infectious symptomatic state (days).	Fixed: 2.9	From Liu et al., 2020b Applicable only until quarantine starts on 5th Feb
${\displaystyle \frac{1}{\mu }}$	Mean delay between onset of symptomatic disease and symptom-based testing and removal (days).	Fixed: 1	Assumed. Applicable only after quarantine starts on 5th Feb.
${\displaystyle \frac{1}{\eta }}$	Mean duration of test positivity following recovery (days)	Fixed: 7	From Woelfel et al., 2020
${\displaystyle \varphi }$	Proportion of symptomatic cases with a reported onset date	Fixed: 0.661 (199/314)	From Mizumoto et al., 2020; Nishiura, 2020
${\displaystyle f(t)}$	Rate of symptom-agnostic testing and removal (1/days)	Fixed: Calculated	From Mizumoto et al., 2020 Calculated using the number of tests administered per day amongst individuals not reporting symptoms (see Appendix 1)
${\displaystyle N^{(p)}}$	Total number of passengers on the ship as at start of quarantine on 5th Feb	Fixed: 2666	From NIID, 2020
${\displaystyle N^{(c)}}$	Total number of crew on the ship as at start of quarantine on 5th Feb	Fixed: 1045	From NIID, 2020