For the study, researchers compared COVID-19 rates for counties on either side of the Iowa/Illinois border and found what happens when one state issues a stay-at-home order and the other doesn't.
FRIDAY, May 15, 2020 (HealthDay News) -- Statewide stay-at-home orders appear to help slow the spread of COVID-19 above and beyond other steps like banning large gatherings and closing non-essential businesses.
That's the suggestion from a new cross-border study.
Certain counties in Iowa -- one of five states that didn't issue a stay-at-home order for its citizens -- experienced a 30% greater increase in COVID-19 cases compared to counties right across the border in Illinois, which did issue such an order, the researchers reported.
"It does line up with a lot of other evidence that's coming up from other national studies," said senior researcher George Wehby, a professor of health management and policy with the University of Iowa College of Public Health. "Overall, there's evidence the more restrictive measures were associated with greater declines in COVID case growth."
For this study, Wehby and a colleague compared COVID-19 rates for counties on either side of the Iowa/Illinois border. "Border counties serve as nice controls because they tend to be somewhat similar," Wehby said.
As the pandemic unfolded, Iowa issued a series of social distancing orders. The state banned gatherings and closed bars and restaurants, then closed non-essential businesses, and then closed all primary and secondary schools.
But Iowa did not issue a broad shelter-in-place order directing residents to stay home unless absolutely necessary, a step taken by Illinois on March 21.