Changing social contact patterns among US workers during the COVID-19 pandemic: April 2020 to December 2021
Moses C. Kiti,
Obianuju G. Aguolu,
Alana Zelaya,
Holin Y. Chen,
Noureen Ahmed,
Jonathan Batross,
Carol Y. Liu,
Kristin N. Nelson,
Samuel M. Jenness,
Alessia Melegaro,
Faruque Ahmed,
Fauzia Malik,
Saad B. Omer,
Ben A. Lopman
Affiliations
Moses C. Kiti
Rollins School of Public Health, Emory University, GA, USA; Correspondence to: Emory University Rollins School of Public Health, 1518 Clifton Rd, Atlanta, GA 30322, USA.
Obianuju G. Aguolu
Yale Institute for Global Health, Yale University, CT, USA; Yale School of Medicine, Yale University, CT, USA
Alana Zelaya
Rollins School of Public Health, Emory University, GA, USA
Holin Y. Chen
Rollins School of Public Health, Emory University, GA, USA
Noureen Ahmed
Yale Institute for Global Health, Yale University, CT, USA
Jonathan Batross
Rollins School of Public Health, Emory University, GA, USA
Carol Y. Liu
Rollins School of Public Health, Emory University, GA, USA
Kristin N. Nelson
Rollins School of Public Health, Emory University, GA, USA
Samuel M. Jenness
Rollins School of Public Health, Emory University, GA, USA
Alessia Melegaro
DONDENA Centre for Research in Social Dynamics and Public Policy, Bocconi University, Italy
Faruque Ahmed
Division of Global Migration and Quarantine, Centers for Disease Control and Prevention, Atlanta, GA, USA
Fauzia Malik
Yale Institute for Global Health, Yale University, CT, USA
Saad B. Omer
Yale Institute for Global Health, Yale University, CT, USA; Yale School of Medicine, Yale University, CT, USA
Ben A. Lopman
Rollins School of Public Health, Emory University, GA, USA
Non-pharmaceutical interventions minimize social contacts, hence the spread of respiratory pathogens such as influenza and SARS-CoV-2. Globally, there is a paucity of social contact data from the workforce. In this study, we quantified two-day contact patterns among USA employees. Contacts were defined as face-to-face conversations, involving physical touch or proximity to another individual and were collected using electronic self-kept diaries. Data were collected over 4 rounds from 2020 to 2021 during the COVID-19 pandemic. Mean (standard deviation) contacts reported by 1456 participants were 2.5 (2.5), 8.2 (7.1), 9.2 (7.1) and 10.1 (9.5) across round 1 (April–June 2020), 2 (November 2020–January 2021), 3 (June–August 2021), and 4 (November–December 2021), respectively. Between round 1 and 2, we report a 3-fold increase in the mean number of contacts reported per participant with no major increases from round 2–4. We then modeled SARS-CoV-2 transmission at home, work, and community settings. The model revealed reduced relative transmission in all settings in round 1. Subsequently, transmission increased at home and in the community but remained exceptionally low in work settings. To accurately parameterize models of infection transmission and control, we need empirical social contact data that capture human mixing behavior across time.
