Most states enacted shelter-in-place orders when mitigating the coronavirus disease 2019 (COVID-19) pandemic. Emerging evidence indicates that these orders have reduced COVID-19 cases. Using data starting at different dates in March and going through May 15, 2020, we examined the effects of shelter-in-place orders on daily growth rates of both COVID-19 deaths and hospitalizations, using event study models. We found that shelter-in-place orders reduced both the daily mortality growth rate nearly three weeks after their enactment and the daily growth rate of hospitalizations two weeks after their enactment. After forty-two days from enactment, the daily mortality growth rate declined by up to 6.1 percentage points. Projections suggest that as many as 250,000-370,000 deaths were possibly averted by May 15 in the forty-two states plus Washington, D.C., that had statewide shelter-in-place orders. The daily hospitalization growth rate examined in nineteen states with shelter-in-place orders and three states without them that had data on hospitalizations declined by up to 8.4 percentage points after forty-two days. This evidence suggests that shelter-in-place orders have been effective in reducing the daily growth rates of COVID-19 deaths and hospitalizations.
Keywords: COVID-19; Diseases; Government programs and policies; Hospital care; Hospital quality; Hospital stays; Hospitalizations; Mortality; Pandemics; Patients; Policy mandates; Shelter in place; State mandates; Stay at home; coronavirus; health policy; hospitals; nursing homes.