Health and Economic Impacts of Lockdown Policies in the Early Stage of COVID-19 in the United States.

This article focuses on quantitatively analyzing the health and economic impacts of COVID-19 lockdown policies implemented across all 50 U.S. states and the District of Columbia during March–June 2020. Using a compartmental SEIRS (Susceptible-Exposed-Infected-Recovered-Susceptible) epidemiologic model calibrated with detailed state-level data—including testing, hospitalizations, mobility from cellphone data, and demographics—the study estimates quality-adjusted life years (QALYs) saved and costs incurred under actual, counterfactual stricter, and no-intervention scenarios. Results indicate that stricter lockdown policies generally would have saved more QALYs and reduced total costs compared to the policies enacted, with significant heterogeneity across states and greater benefits observed in high-risk populations (those aged 65 or older and Black/Hispanic individuals). The study also incorporates a longitudinal mixed-effect regression model to adjust disease transmission rates based on policy intensity, duration, sociodemographic factors, mobility, and testing, and performs extensive sensitivity analyses confirming the robustness of findings. These insights aim to assist federal and state authorities in tailoring pandemic response policies more effectively and have implications for managing future fast-spreading infectious diseases.