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. 2020 Mar;25(10):2000180.
doi: 10.2807/1560-7917.ES.2020.25.10.2000180.

Estimating the asymptomatic proportion of coronavirus disease 2019 (COVID-19) cases on board the Diamond Princess cruise ship, Yokohama, Japan, 2020

Kenji Mizumoto  1   2   3 , Katsushi Kagaya  2   4 , Alexander Zarebski  5 , Gerardo Chowell  3
Affiliations

Estimating the asymptomatic proportion of coronavirus disease 2019 (COVID-19) cases on board the Diamond Princess cruise ship, Yokohama, Japan, 2020

Kenji Mizumoto et al. Euro Surveill. 2020 Mar.

Erratum in

  • Author's correction for Euro Surveill. 2020;25(10).
    Eurosurveillance editorial team. Eurosurveillance editorial team. Euro Surveill. 2020 Jun;25(22):20200604c. doi: 10.2807/1560-7917.ES.2020.25.22.20200604c. Euro Surveill. 2020. PMID: 32524952 Free PMC article. No abstract available.

Abstract

On 5 February 2020, in Yokohama, Japan, a cruise ship hosting 3,711 people underwent a 2-week quarantine after a former passenger was found with COVID-19 post-disembarking. As at 20 February, 634 persons on board tested positive for the causative virus. We conducted statistical modelling to derive the delay-adjusted asymptomatic proportion of infections, along with the infections' timeline. The estimated asymptomatic proportion was 17.9% (95% credible interval (CrI): 15.5-20.2%). Most infections occurred before the quarantine start.

Keywords: COVID-19; Japan; asymptomatic; corona; outbreak; quarantine.

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Conflict of interest statement

Conflict of interest: None declared.

Figures

Figure
Figure
Age distribution of reported coronavirus disease 2019 cases on board the Diamond Princess cruise ship stratified by sex, Yokohama, Japan, 20 February 2020 (n = 634 cases)
See this image and copyright information in PMC

References

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