TY - JOUR

T1 - Behavioral factors associated with SARS-CoV-2 infection

AU - Cajar, Mille Dybdal

AU - Tan, Florence Chia Chin

AU - Boisen, Mogens Karsboel

AU - Krog, Sebastian Moretto

AU - Nolsoee, Runa

AU - Christensen, Helle Collatz

AU - Andersen, Mikkel Porsborg

AU - Moeller, Amalie Lykkemark

AU - Gerds, Thomas Alexander

AU - Pedersen-Bjergaard, Ulrik

AU - Lindegaard, Birgitte

AU - Kristensen, Peter Lommer

AU - Christensen, Thomas Broe

AU - Torp-Pedersen, Christian

AU - Lendorf, Maria Elisabeth

PY - 2022

Y1 - 2022

N2 - Objective To study the association between behavioural factors and incidence rates of SARS-CoV-2 infection.Design Case–control web-based questionnaire study.Setting Questionnaire data were collected in the Capital Region of Denmark in December 2020 when limited restrictions were in place, while the number of daily SARS-CoV-2 cases increased rapidly.Participants 8913 cases of laboratory-confirmed SARS-CoV-2 infection were compared with two groups of controls: (1) 34 063 individuals with a negative SARS-CoV-2 test from the same date (negative controls, NCs) and 2) 25 989 individuals who had never been tested for a SARS-CoV-2 infection (untested controls, UC). Controls were matched on sex, age, test date and municipality.Exposure Activities during the 14 days prior to being tested positive for SARS-CoV-2 or during the same period for matched controls and precautions taken during the entire pandemic.Main outcomes and measures SARS-CoV-2 infection incidence rate ratios (IRR).Results Response rate was 41.4% (n=93 121). Using public transportation, grocery shopping (IRR: NC: 0.52; UC: 0.63) and outdoor sports activities (NC: 0.75; UC: 0.96) were not associated with increased rate of SARS-CoV-2 infection. Most precautions, for example, using hand sanitizer (NC: 0.79; UC: 0.98), physical distancing (NC: 0.79; UC: 0.82) and avoiding handshakes (NC: 0.74; UC: 0.77), were associated with a lower rate of infection. Activities associated with many close contacts, especially indoors, increased rate of infection. Except for working from home, all types of occupation were linked to increased rate of infection.Conclusions In a community setting with moderate restrictions, activities such as using public transportation and grocery shopping with the relevant precautions were not associated with an increased rate of SARS-CoV-2 infection. Exposures and activities where safety measures are difficult to maintain might be important risk factors for infection. These findings may help public health authorities tailor their strategies for limiting the spread of SARS-CoV-2.

AB - Objective To study the association between behavioural factors and incidence rates of SARS-CoV-2 infection.Design Case–control web-based questionnaire study.Setting Questionnaire data were collected in the Capital Region of Denmark in December 2020 when limited restrictions were in place, while the number of daily SARS-CoV-2 cases increased rapidly.Participants 8913 cases of laboratory-confirmed SARS-CoV-2 infection were compared with two groups of controls: (1) 34 063 individuals with a negative SARS-CoV-2 test from the same date (negative controls, NCs) and 2) 25 989 individuals who had never been tested for a SARS-CoV-2 infection (untested controls, UC). Controls were matched on sex, age, test date and municipality.Exposure Activities during the 14 days prior to being tested positive for SARS-CoV-2 or during the same period for matched controls and precautions taken during the entire pandemic.Main outcomes and measures SARS-CoV-2 infection incidence rate ratios (IRR).Results Response rate was 41.4% (n=93 121). Using public transportation, grocery shopping (IRR: NC: 0.52; UC: 0.63) and outdoor sports activities (NC: 0.75; UC: 0.96) were not associated with increased rate of SARS-CoV-2 infection. Most precautions, for example, using hand sanitizer (NC: 0.79; UC: 0.98), physical distancing (NC: 0.79; UC: 0.82) and avoiding handshakes (NC: 0.74; UC: 0.77), were associated with a lower rate of infection. Activities associated with many close contacts, especially indoors, increased rate of infection. Except for working from home, all types of occupation were linked to increased rate of infection.Conclusions In a community setting with moderate restrictions, activities such as using public transportation and grocery shopping with the relevant precautions were not associated with an increased rate of SARS-CoV-2 infection. Exposures and activities where safety measures are difficult to maintain might be important risk factors for infection. These findings may help public health authorities tailor their strategies for limiting the spread of SARS-CoV-2.

KW - COVID-19

KW - Epidemiology

KW - INFECTIOUS DISEASES

U2 - 10.1136/bmjopen-2021-056393

DO - 10.1136/bmjopen-2021-056393

M3 - Journal article

C2 - 36691250

VL - 12

JO - BMJ Open

JF - BMJ Open

SN - 2044-6055

IS - 6

ER -