Effect of the timing of stay-at-home orders on COVID-19 infections in the United States of America

Abstract The current COVID-19 pandemic has sparked growing global interest in understanding the spread and outcome of the virus. From previous pandemics, we have learned that several demographic, geographic, and socio-economic factors may play a role in increasing risk of infection. Our objective was to examine the association of timing of mandated stay-at-home orders at the county-level with COVID-19 cases, daily case rate and mortality in the United States of America (USA). Publicly available data were used to perform a cross-sectional study of USA counties with > 100,000 population, and at least 50 confirmed cases per 100,000 people as of May 24, 2020. The three outcome variables were: total cases/100,000, daily case rate (DCR), and total deaths/100,000. Out of 3142 USA counties, 569 met the inclusion criteria. Of all variables, the timing of state-mandated stay-at-home order had the most significant effect on all three outcomes after adjusting for multiple socio-demographic, geographic and health related factors. Additional factors with significant association with increased cases and deaths include population density, housing problem, unemployment, African American race, and age > 65. Policymakers at the local level must take this into consideration while planning for interventions to prevent the spread of COVID-19.