This study uses state public health department data to describe trends in COVID-19 hospitalizations before and after state executive stay-at-home orders issued in March and April 2020 in Colorado, Minnesota, Ohio, and Virginia, and compares projected vs observed admissions to estimate associations.
In all 4 states, cumulative hospitalizations up to and including the median effective date of a stay-at-home order closely fit and favored an exponential function over a linear fit (R2 = 0.973 vs 0.695 in Colorado; 0.965 vs 0.865 in Minnesota; 0.98 vs 0.803 in Ohio; 0.994 vs 0.775 in Virginia). However, after the median effective date, observed hospitalization growth rates deviated from projected exponential growth rates with slower growth in all 4 states. Observed hospitalizations consistently fell outside of the 95% prediction bands of the projected exponential growth curve.
For example, Minnesota’s residents were mandated to stay at home starting March 28. On April 13, 5 days after the median effective date, the cumulative projected hospitalizations were 988 and the actual hospitalizations were 361. In Virginia, projected hospitalizations 5 days after the median effective date were 2335 and actual hospitalizations were 1048.
In other words, there was an association between the implementation of statewide stay-at-home orders and a reduction in the number of people hospitalized for COVID-19 in these states.
A variety of additional factors that were not examined in this study may have contributed to the slowing hospitalization rate, including a declaration of national emergency; school closures; a growing, general awareness about distancing; and good hand hygiene practices.
