Abstract:Objective:Presenteeism is an expensive and challenging problem in the healthcare industry. In anticipation of the staffing challenges expected with the COVID-19 pandemic, we examined a decade of payroll data for a healthcare workforce. We aimed to determine the effect of seasonal influenza-like illness (ILI) on absences to support COVID-19 staffing plans.Design:Retrospective cohort study.Setting:Large academic medical center in the United States.Participants:Employees of the academic medical center who were on payroll between the years of 2009 and 2019.Methods:Biweekly institutional payroll data was evaluated for unscheduled absences as a marker for acute illness-related work absences. Linear regression models, stratified by payroll status (salaried vs hourly employees) were developed for unscheduled absences as a function of local ILI.Results:Both hours worked and unscheduled absences were significantly related to the community prevalence of influenza-like illness in our cohort. These effects were stronger in hourly employees.Conclusions:Organizations should target their messaging at encouraging salaried staff to stay home when ill.