US COVID-19 cases rising again, doubling over three weeks

Patrons enjoy cold tropical cocktails in the tiny interior of the Tiki-Ti bar July 7 as it reopens on Sunset Boulevard in Los Angeles. (AP Photo/Damian Dovarganes, File)

The COVID-19 curve in the U.S. is rising again after months of decline, with the number of new cases per day doubling over the past three weeks, driven by the fast-spreading delta variant, lagging vaccination rates and Fourth of July gatherings.