Association between social activities and risk of COVID-19 in a cohort of healthcare personnel

Abstract

Objective: Previous studies have linked social behaviors to COVID-19 risk in the general population. The impact of these behaviors among healthcare personnel, who face higher workplace exposure risks and possess greater prevention awareness, remains less explored.

Design: We conducted a Prospective cohort study from December 2021 to May 2022, using monthly surveys. Exposures included (1) a composite of nine common social activities in the past month and (2) similarity of social behavior compared to pre-pandemic. Outcomes included self-reported SARS-CoV-2 infection (primary)and testing for SARS-CoV-2 (secondary). Mixed-effect logistic regression assessed the association between social behavior and outcomes, adjusting for baseline and time-dependent covariates. To account for missed surveys, we employed inverse probability-of-censoring weighting with a propensity score approach.

Setting: An academic healthcare system.

Participants: Healthcare personnel.

Results: Of 1,302 healthcare personnel who completed ≥2 surveys, 244 reported ≥1 positive test during the study, resulting in a cumulative incidence of 19%. More social activities in the past month and social behavior similar to pre-pandemic levels were associated with increased likelihood of SARS-CoV-2 infection (recent social activity composite: OR = 1.11, 95% CI 1.02-1.21; pre-pandemic social similarity: OR = 1.14, 95% CI 1.07-1.21). Neither was significantly associated with testing for SARS-CoV-2.

Conclusions: Healthcare personnel social behavior outside work was associated with a higher risk for COVID-19. To protect the hospital workforce, risk mitigation strategies for healthcare personnel should focus on both the community and workplace.

Figure 1.

Self-reported SARS-CoV-2 test results over time. The left y-axis corresponds to the number of self-reported SARS-CoV-2 test results, represented by the gray bars for negative results and the red bars for positive results. The right y-axis tracks the cumulative number of new SARS-CoV-2 infections, depicted by the red line curve.

Figure 2.

Temporal trends of individual social activities. Social activities were ordered by the overall rate. The months on the x-axis refer to the time when the participants completed the survey, reflecting the social activities they had engaged in during the preceding months. Statistically significant changes in the prevalence of social activity compared to the baseline (December) are indicated by “+” for increases and “−” for decreases, appended to the survey month.

Figure 3.

Effect of recent social activity composite, pre-pandemic social similarity, and recent individual social activities, on SARS-CoV-2 infection among healthcare personnel. Covariates included in the models: age, gender, clinical role, work location, self-rated health, any comorbidities, household condition, calendar month of taking survey, months since last survey, months since recent COVID vaccine, months since recent SARS-CoV-2 infection, and recent illness.