1. Epidemiology and Global Health
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Quantifying the impact of quarantine duration on COVID-19 transmission

  1. Peter Ashcroft  Is a corresponding author
  2. Sonja Lehtinen
  3. Daniel C Angst
  4. Nicola Low
  5. Sebastian Bonhoeffer  Is a corresponding author
  1. ETH Zurich, Switzerland
  2. University of Bern, Switzerland
Research Article
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Cite this article as: eLife 2021;10:e63704 doi: 10.7554/eLife.63704

Abstract

The large number of individuals placed into quarantine because of possible SARS CoV-2 exposure has high societal and economic costs. There is ongoing debate about the appropriate duration of quarantine, particularly since the fraction of individuals who eventually test positive is perceived as being low. We use empirically determined distributions of incubation period, infectivity, and generation time to quantify how the duration of quarantine affects onward transmission from traced contacts of confirmed SARS-CoV-2 cases and from returning travellers. We also consider the roles of testing followed by release if negative (test-and-release), reinforced hygiene, adherence, and symptoms in calculating quarantine efficacy. We show that there are quarantine strategies based on a test-and-release protocol that, from an epidemiological viewpoint, perform almost as well as a 10 day quarantine, but with fewer person days spent in quarantine. The findings apply to both travellers and contacts, but the specifics depend on the context.

Article and author information

Author details

  1. Peter Ashcroft

    Institute of Integrative Biology, ETH Zurich, Zurich, Switzerland
    For correspondence
    peter.ashcroft@env.ethz.ch
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4067-7692
  2. Sonja Lehtinen

    Department of Environmental Systems Science, ETH Zurich, Zurich, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-4236-828X
  3. Daniel C Angst

    Institute of Integrative Biology, ETH Zurich, Zurich, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-6512-4595
  4. Nicola Low

    University of Bern, Bern, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  5. Sebastian Bonhoeffer

    Institute of Integrative Biology, ETH Zurich, Zurich, Switzerland
    For correspondence
    seb@env.ethz.ch
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-8052-3925

Funding

H2020 European Research Council (EpiPose,101003688)

  • Nicola Low

Swiss National Science Foundation (176233)

  • Nicola Low

Swiss National Science Foundation (176401)

  • Sebastian Bonhoeffer

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Deborah Cromer, University of New South Wales, Australia

Publication history

  1. Received: October 2, 2020
  2. Accepted: February 4, 2021
  3. Accepted Manuscript published: February 5, 2021 (version 1)

Copyright

© 2021, Ashcroft et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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