Between 2013 and 2017, 64 rural hospitals across the country shut down, more than double the rate of the previous five years. More than half of closures since 2010 were in the South, where most states have chosen not to expand Medicaid, as allowed for under the Affordable Care Act.

One such hospital was Cumberland River Hospital in the Middle Tennessee town of Celina, population 1,463, where Natalie Boone serves as director of Clay County Emergency Medical Services. On March 1, the hospital ceased to be.

About two and a half years ago, Boone’s mother, Marilyn Boone, was ailing. She’d been sick...