California mask mandates return as Delta cases surge

A surge in Covid-19 infections, driven by the Delta variant, has prompted San Francisco and six other counties in the Bay Area to reimpose mask mandates for indoor spaces, less than two months after the highly vaccinated region hoped it was beginning a return to normal.

San Francisco’s infection rates have surged to nearly 20 times what they were at their lowest point in June. The US has seen continued rises in infections, with federal officials acknowledging that the new Delta variant is as contagious as chickenpox.