BUCKINGHAM COUNTY, Va. — Most people in this rural logging area have only one choice when they need medical care: the Central Virginia Community Health Center. On most days, at least 200 people show up at the center seeking treatment for maladies ranging from sore throats to depression to cavities.

The health center typically has four doctors on duty, but the clinical director, Dr. Randall Bayshore, says his staff would never meet local demand if it weren’t for the two nurse practitioners who provide the same care, to the same number of patients, as the doctors.

Buckingham County is one of roughly 5,800 U.S. communities, with about 55 million residents, that have a shortage of primary care physicians. In these places, many residents are forced to forgo regular checkups and treatment for chronic diseases such as hypertension and diabetes — harming their overall health.