Evaluating COVID-19 Lockdown and Reopening Scenarios For Georgia, Florida, and Mississippi

Background: The United States has been particularly hard-hit by COVID-19, accounting for almost one third of global cases and one quarter of global deaths from the disease that have been reported as of May 10, 2020. We extended our agent-based model for COVID-19 transmission [1] to study the effect of alternative lockdown and reopening policies on disease dynamics in Georgia, Florida, and Mississippi. Specifically, for each state we simulated the spread of the disease had the state enforced its lockdown approximately one week earlier than it did. We also simulated Georgia’s reopening plan under various levels of physical distancing if enacted in each state, making projections until June 15, 2020.Methods: We used an agent-based SEIR model that uses population-specific age distribution, household structure, contact patterns, and comorbidity rates to perform tailored simulations for each region. The model was first calibrated to each state using publicly available COVID-19 death data as of April 23, then implemented to simulate given lockdown or reopening policies. Results: Our model estimated that imposing lockdowns one week earlier could have resulted in hundreds fewer COVID-19 related deaths in the context of all three states. These estimates underscore that early action may be imperative in the event of a second wave of infection. Further, simulating Georgia’s plan to reopen as of April 27, our model found that a reopening policy that includes physical distancing to ensure no more than 25% of pre-lockdown contact rates at reopened businesses could allow limited economic activity to resume in any of the three states, while also …