SARS-CoV-2 Transmission and Control Among Healthcare Workers in a Hospital Setting: A Modelling Study

Background: Development of strategies for mitigating COVID-19 outbreak in a hospital setting is a public health priority. Methods: We developed an individual-based model for COVID-19 transmission among healthcare workers (HCWs) in a hospital setting. We calibrated the model using data of a COVID-19 outbreak in a hospital unit in Wuhan. The calibrated model was used to simulate different intervention scenarios and estimate the impact of different interventions on outbreak size and workday loss. Findings: We estimated that work-related stress increases susceptibility to COVID-19 infection among HCWs by 52% (90% CrI: 16·4% - 93·0%). The use of high efficacy facial masks was shown to be able to reduce infection cases and workday loss by 80% (90% CrI: 73·1% - 85·7%) and 87% (CrI: 80·0% - 92·5%), respectively. The use of social distancing alone, through reduced contacts between HCWs, had a marginal impact on the outbreak. A strict quarantine policy with isolation of symptomatic cases and a high fraction of pre-symptomatic cases (via contact tracing or high test rate), could only prolong outbreak duration with minimal impact on the outbreak size. Our results indicated that a quarantine policy should be coupled with other interventions to achieve its effect. The effectiveness of all these interventions was shown to increase with their early implementation. Interpretation: Our analysis shows that a COVID-19 outbreak in a hospital’s non-COVID-19 unit can be controlled or mitigated by the use of existing non-pharmaceutical measures. Funding Statement: This work was supported by the National Science Foundation RAPID Award [grant number DEB-2028631 to QH, AM, and DG], the National Science Foundation RAPID Award [grant number DEB-2028632 to MN], and the Fundamental Research Funds for the Central Universities [grant number 2020kfyXGYJ010 to XJ]. Declaration of Interests: All authors declare no competing interests.