TY - JOUR
T1 - Outbreaks of COVID-19 variants in US prisons
T2 - a mathematical modelling analysis of vaccination and reopening policies
AU - Ryckman, Theresa
AU - Chin, Elizabeth T.
AU - Prince, Lea
AU - Leidner, David
AU - Long, Elizabeth
AU - Studdert, David M.
AU - Salomon, Joshua A.
AU - Alarid-Escudero, Fernando
AU - Andrews, Jason R.
AU - Goldhaber-Fiebert, Jeremy D.
N1 - Funding Information: This research was supported by Stanford's COVID-19 Emergency Response Fund, established with a gift from the Horowitz Family Foundation; the National Institute on Drug Abuse (R37-DA15612); the Centers for Disease Control and Prevention (through the Council of State and Territorial Epidemiologists, NU38OT000297-02); the National Science Foundation's Graduate Research Fellowship (DGE-1656518); the Stanford Graduate Fellowship in Science and Engineering, and the Open Society Foundations (OR2020-69521). Advanced Micro Devices (Santa Clara, CA, USA) provided a donation of servers. This material is based upon work supported by the National Science Foundation Graduate Research Fellowship Program (DGE-1656518). Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation. We thank staff members at the CDCR for providing data and assistance with interpretation of study results. We would also like to thank Liesl Hagan (US Centers for Disease Control and Prevention, Atlanta, GA, USA) and Robert Canning (CDCR, Sacramento, CA, USA) for sharing their expertise to help to inform our selection of prisons for this analysis. We also acknowledge assistance from other members of the Stanford-CIDE Coronavirus Simulation Modelling consortium. Funding Information: This research was supported by Stanford's COVID-19 Emergency Response Fund, established with a gift from the Horowitz Family Foundation; the National Institute on Drug Abuse (R37-DA15612); the Centers for Disease Control and Prevention (through the Council of State and Territorial Epidemiologists, NU38OT000297-02); the National Science Foundation's Graduate Research Fellowship (DGE-1656518); the Stanford Graduate Fellowship in Science and Engineering, and the Open Society Foundations (OR2020-69521). Advanced Micro Devices (Santa Clara, CA, USA) provided a donation of servers. This material is based upon work supported by the National Science Foundation Graduate Research Fellowship Program (DGE-1656518). Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation. We thank staff members at the CDCR for providing data and assistance with interpretation of study results. We would also like to thank Liesl Hagan (US Centers for Disease Control and Prevention, Atlanta, GA, USA) and Robert Canning (CDCR, Sacramento, CA, USA) for sharing their expertise to help to inform our selection of prisons for this analysis. We also acknowledge assistance from other members of the Stanford-CIDE Coronavirus Simulation Modelling consortium. Publisher Copyright: © 2021 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY-NC-ND 4.0 license
PY - 2021/10/1
Y1 - 2021/10/1
N2 - Background: Residents of prisons have experienced disproportionate COVID-19-related health harms. To control outbreaks, many prisons in the USA restricted in-person activities, which are now resuming even as viral variants proliferate. This study aims to use mathematical modelling to assess the risks and harms of COVID-19 outbreaks in prisons under a range of policies, including resumption of activities. Methods: We obtained daily resident-level data for all California state prisons from Jan 1, 2020, to May 15, 2021, describing prison layouts, housing status, sociodemographic and health characteristics, participation in activities, and COVID-19 testing, infection, and vaccination status. We developed a transmission-dynamic stochastic microsimulation parameterised by the California data and published literature. After an initial infection is introduced to a prison, the model evaluates the effect of various policy scenarios on infections and hospitalisations over 200 days. Scenarios vary by vaccine coverage, baseline immunity (0%, 25%, or 50%), resumption of activities, and use of non-pharmaceutical interventions (NPIs) that reduce transmission by 75%. We simulated five prison types that differ by residential layout and demographics, and estimated outcomes with and without repeated infection introductions over the 200 days. Findings: If a viral variant is introduced into a prison that has resumed pre-2020 contact levels, has moderate vaccine coverage (ranging from 36% to 76% among residents, dependent on age, with 40% coverage for staff), and has no baseline immunity, 23–74% of residents are expected to be infected over 200 days. High vaccination coverage (90%) coupled with NPIs reduces cumulative infections to 2–54%. Even in prisons with low room occupancies (ie, no more than two occupants) and low levels of cumulative infections (ie, <10%), hospitalisation risks are substantial when these prisons house medically vulnerable populations. Risks of large outbreaks (>20% of residents infected) are substantially higher if infections are repeatedly introduced. Interpretation: Balancing benefits of resuming activities against risks of outbreaks presents challenging trade-offs. After achieving high vaccine coverage, prisons with mostly one-to-two-person cells that have higher baseline immunity from previous outbreaks can resume in-person activities with low risk of a widespread new outbreak, provided they maintain widespread NPIs, continue testing, and take measures to protect the medically vulnerable. Funding: Horowitz Family Foundation, National Institute on Drug Abuse, Centers for Disease Control and Prevention, National Science Foundation, Open Society Foundation, Advanced Micro Devices.
AB - Background: Residents of prisons have experienced disproportionate COVID-19-related health harms. To control outbreaks, many prisons in the USA restricted in-person activities, which are now resuming even as viral variants proliferate. This study aims to use mathematical modelling to assess the risks and harms of COVID-19 outbreaks in prisons under a range of policies, including resumption of activities. Methods: We obtained daily resident-level data for all California state prisons from Jan 1, 2020, to May 15, 2021, describing prison layouts, housing status, sociodemographic and health characteristics, participation in activities, and COVID-19 testing, infection, and vaccination status. We developed a transmission-dynamic stochastic microsimulation parameterised by the California data and published literature. After an initial infection is introduced to a prison, the model evaluates the effect of various policy scenarios on infections and hospitalisations over 200 days. Scenarios vary by vaccine coverage, baseline immunity (0%, 25%, or 50%), resumption of activities, and use of non-pharmaceutical interventions (NPIs) that reduce transmission by 75%. We simulated five prison types that differ by residential layout and demographics, and estimated outcomes with and without repeated infection introductions over the 200 days. Findings: If a viral variant is introduced into a prison that has resumed pre-2020 contact levels, has moderate vaccine coverage (ranging from 36% to 76% among residents, dependent on age, with 40% coverage for staff), and has no baseline immunity, 23–74% of residents are expected to be infected over 200 days. High vaccination coverage (90%) coupled with NPIs reduces cumulative infections to 2–54%. Even in prisons with low room occupancies (ie, no more than two occupants) and low levels of cumulative infections (ie, <10%), hospitalisation risks are substantial when these prisons house medically vulnerable populations. Risks of large outbreaks (>20% of residents infected) are substantially higher if infections are repeatedly introduced. Interpretation: Balancing benefits of resuming activities against risks of outbreaks presents challenging trade-offs. After achieving high vaccine coverage, prisons with mostly one-to-two-person cells that have higher baseline immunity from previous outbreaks can resume in-person activities with low risk of a widespread new outbreak, provided they maintain widespread NPIs, continue testing, and take measures to protect the medically vulnerable. Funding: Horowitz Family Foundation, National Institute on Drug Abuse, Centers for Disease Control and Prevention, National Science Foundation, Open Society Foundation, Advanced Micro Devices.
UR - http://www.scopus.com/inward/record.url?scp=85115352501&partnerID=8YFLogxK
U2 - https://doi.org/10.1016/S2468-2667(21)00162-6
DO - https://doi.org/10.1016/S2468-2667(21)00162-6
M3 - Article
C2 - 34364404
SN - 2468-2667
VL - 6
SP - e760-e770
JO - The Lancet. Public health
JF - The Lancet. Public health
IS - 10
ER -