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Using a household-structured branching process to analyse contact tracing in the SARS-CoV-2 pandemic

We explore strategies of contact tracing, case isolation and quarantine of exposed contacts to control the SARS-CoV-2 epidemic using a branching process model with household structure. This structure reflects higher transmission risks among household members than among non-household members. We expl...

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Autores principales: Fyles, Martyn, Fearon, Elizabeth, Overton, Christopher, Wingfield, Tom, Medley, Graham F., Hall, Ian, Pellis, Lorenzo, House, Thomas
Formato: Online Artículo Texto
Lenguaje:English
Publicado: The Royal Society 2021
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8165594/
https://www.ncbi.nlm.nih.gov/pubmed/34053253
http://dx.doi.org/10.1098/rstb.2020.0267
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author Fyles, Martyn
Fearon, Elizabeth
Overton, Christopher
Wingfield, Tom
Medley, Graham F.
Hall, Ian
Pellis, Lorenzo
House, Thomas
author_facet Fyles, Martyn
Fearon, Elizabeth
Overton, Christopher
Wingfield, Tom
Medley, Graham F.
Hall, Ian
Pellis, Lorenzo
House, Thomas
author_sort Fyles, Martyn
collection PubMed
description We explore strategies of contact tracing, case isolation and quarantine of exposed contacts to control the SARS-CoV-2 epidemic using a branching process model with household structure. This structure reflects higher transmission risks among household members than among non-household members. We explore strategic implementation choices that make use of household structure, and investigate strategies including two-step tracing, backwards tracing, smartphone tracing and tracing upon symptom report rather than test results. The primary model outcome is the effect of contact tracing, in combination with different levels of physical distancing, on the growth rate of the epidemic. Furthermore, we investigate epidemic extinction times to indicate the time period over which interventions must be sustained. We consider effects of non-uptake of isolation/quarantine, non-adherence, and declining recall of contacts over time. Our results find that, compared to self-isolation of cases without contact tracing, a contact tracing strategy designed to take advantage of household structure allows for some relaxation of physical distancing measures but cannot completely control the epidemic absent of other measures. Even assuming no imported cases and sustainment of moderate physical distancing, testing and tracing efforts, the time to bring the epidemic to extinction could be in the order of months to years. This article is part of the theme issue ‘Modelling that shaped the early COVID-19 pandemic response in the UK’.
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spelling pubmed-81655942021-06-03 Using a household-structured branching process to analyse contact tracing in the SARS-CoV-2 pandemic Fyles, Martyn Fearon, Elizabeth Overton, Christopher Wingfield, Tom Medley, Graham F. Hall, Ian Pellis, Lorenzo House, Thomas Philos Trans R Soc Lond B Biol Sci Articles We explore strategies of contact tracing, case isolation and quarantine of exposed contacts to control the SARS-CoV-2 epidemic using a branching process model with household structure. This structure reflects higher transmission risks among household members than among non-household members. We explore strategic implementation choices that make use of household structure, and investigate strategies including two-step tracing, backwards tracing, smartphone tracing and tracing upon symptom report rather than test results. The primary model outcome is the effect of contact tracing, in combination with different levels of physical distancing, on the growth rate of the epidemic. Furthermore, we investigate epidemic extinction times to indicate the time period over which interventions must be sustained. We consider effects of non-uptake of isolation/quarantine, non-adherence, and declining recall of contacts over time. Our results find that, compared to self-isolation of cases without contact tracing, a contact tracing strategy designed to take advantage of household structure allows for some relaxation of physical distancing measures but cannot completely control the epidemic absent of other measures. Even assuming no imported cases and sustainment of moderate physical distancing, testing and tracing efforts, the time to bring the epidemic to extinction could be in the order of months to years. This article is part of the theme issue ‘Modelling that shaped the early COVID-19 pandemic response in the UK’. The Royal Society 2021-07-19 2021-05-31 /pmc/articles/PMC8165594/ /pubmed/34053253 http://dx.doi.org/10.1098/rstb.2020.0267 Text en © 2021 The Authors. https://creativecommons.org/licenses/by/4.0/Published by the Royal Society under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/4.0/ (https://creativecommons.org/licenses/by/4.0/) , which permits unrestricted use, provided the original author and source are credited.
spellingShingle Articles
Fyles, Martyn
Fearon, Elizabeth
Overton, Christopher
Wingfield, Tom
Medley, Graham F.
Hall, Ian
Pellis, Lorenzo
House, Thomas
Using a household-structured branching process to analyse contact tracing in the SARS-CoV-2 pandemic
title Using a household-structured branching process to analyse contact tracing in the SARS-CoV-2 pandemic
title_full Using a household-structured branching process to analyse contact tracing in the SARS-CoV-2 pandemic
title_fullStr Using a household-structured branching process to analyse contact tracing in the SARS-CoV-2 pandemic
title_full_unstemmed Using a household-structured branching process to analyse contact tracing in the SARS-CoV-2 pandemic
title_short Using a household-structured branching process to analyse contact tracing in the SARS-CoV-2 pandemic
title_sort using a household-structured branching process to analyse contact tracing in the sars-cov-2 pandemic
topic Articles
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8165594/
https://www.ncbi.nlm.nih.gov/pubmed/34053253
http://dx.doi.org/10.1098/rstb.2020.0267
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