TY - JOUR
T1 - Household Exposure to Severe Acute Respiratory Syndrome Coronavirus 2 and Association With Coronavirus Disease 2019 Severity
T2 - a Danish nationwide cohort study
AU - Broccia, Marcella
AU - de Knegt, Victoria Elizabeth
AU - Mills, Elisabeth Helen Anna
AU - Møller, Amalie Lykkemark
AU - Gnesin, Filip
AU - Fischer, Thea K
AU - Zylyftari, Nertila
AU - Blomberg, Stig Nikolaj
AU - Andersen, Mikkel Porsborg
AU - Schou, Morten
AU - Fosbøl, Emil
AU - Kragholm, Kristian
AU - Christensen, Helle Collatz
AU - Polcwiartek, Laura Bech
AU - Phelps, Matthew
AU - Køber, Lars
AU - Torp-Pedersen, Christian
N1 - © The Author(s) 2021. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.
PY - 2022/1/1
Y1 - 2022/1/1
N2 - BACKGROUND: Households are high-risk settings for the transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Severity of coronavirus disease 2019 (COVID-19) is likely associated with the infectious dose of SARS-CoV-2 exposure. We therefore aimed to assess the association between SARS-CoV-2 exposure within households and COVID-19 severity.METHODS: We performed a Danish, nationwide, register-based, cohort study including laboratory-confirmed SARS-CoV-2-infected individuals from 22 February 2020 to 6 October 2020. Household exposure to SARS-CoV-2 was defined as having 1 individual test positive for SARS-CoV-2 within the household. Cox proportional hazards models were used to estimate the association between "critical COVID-19" within and between households with and without secondary cases.RESULTS: From 15 063 multiperson households, 19 773 SARS-CoV-2-positive individuals were included; 11 632 were categorized as index cases without any secondary household cases; 3431 as index cases with secondary cases, that is, 22.8% of multiperson households; and 4710 as secondary cases. Critical COVID-19 occurred in 2.9% of index cases living with no secondary cases, 4.9% of index cases with secondary cases, and 1.3% of secondary cases. The adjusted hazard ratio for critical COVID-19 among index cases vs secondary cases within the same household was 2.50 (95% confidence interval [CI], 1.88-3.34), 2.27 (95% CI, 1.77-2.93) for index cases in households with no secondary cases vs secondary cases, and 1.1 (95% CI, .93-1.30) for index cases with secondary cases vs index cases without secondary cases.CONCLUSIONS: We found no increased hazard ratio of critical COVID-19 among household members of infected SARS-CoV-2 index cases.
AB - BACKGROUND: Households are high-risk settings for the transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Severity of coronavirus disease 2019 (COVID-19) is likely associated with the infectious dose of SARS-CoV-2 exposure. We therefore aimed to assess the association between SARS-CoV-2 exposure within households and COVID-19 severity.METHODS: We performed a Danish, nationwide, register-based, cohort study including laboratory-confirmed SARS-CoV-2-infected individuals from 22 February 2020 to 6 October 2020. Household exposure to SARS-CoV-2 was defined as having 1 individual test positive for SARS-CoV-2 within the household. Cox proportional hazards models were used to estimate the association between "critical COVID-19" within and between households with and without secondary cases.RESULTS: From 15 063 multiperson households, 19 773 SARS-CoV-2-positive individuals were included; 11 632 were categorized as index cases without any secondary household cases; 3431 as index cases with secondary cases, that is, 22.8% of multiperson households; and 4710 as secondary cases. Critical COVID-19 occurred in 2.9% of index cases living with no secondary cases, 4.9% of index cases with secondary cases, and 1.3% of secondary cases. The adjusted hazard ratio for critical COVID-19 among index cases vs secondary cases within the same household was 2.50 (95% confidence interval [CI], 1.88-3.34), 2.27 (95% CI, 1.77-2.93) for index cases in households with no secondary cases vs secondary cases, and 1.1 (95% CI, .93-1.30) for index cases with secondary cases vs index cases without secondary cases.CONCLUSIONS: We found no increased hazard ratio of critical COVID-19 among household members of infected SARS-CoV-2 index cases.
KW - COVID-19
KW - Cohort Studies
KW - Denmark/epidemiology
KW - Family Characteristics
KW - Humans
KW - SARS-CoV-2
KW - transmission
KW - viral load
KW - death
KW - corona
KW - infectious dose
UR - http://www.scopus.com/inward/record.url?scp=85118639712&partnerID=8YFLogxK
U2 - 10.1093/cid/ciab340
DO - 10.1093/cid/ciab340
M3 - Journal article
C2 - 33893489
SN - 1058-4838
VL - 74
SP - 1
EP - 7
JO - Clinical Infectious Diseases
JF - Clinical Infectious Diseases
IS - 1
ER -