SAN DIEGO COUNTY, Calif. — Citing a sharp increase in COVID-19 infection rates since Thanksgiving, the state Wednesday will require mask-wearing in all indoor public settings across California regardless of vaccination status.
The statewide mask mandate will remain in place until Jan. 15. Among the indoor public spaces affected are retail stores, restaurants, theaters, family entertainment centers and government offices that serve the public.
According to the state, roughly half of California's population already lives in a county with a local mask-wearing mandate in place -- but that does not include San Diego County.
In addition to imposing the mask mandate, the state will also toughen the restriction for unvaccinated people who attend indoor "mega-events" of 1,000 people or more, requiring them to receive a negative COVID test within one day of the event if it's a rapid antigen test or within two days for a PCR test. The previous rule required a test within 72 hours of the event.
State officials will also recommend, but not require, that people who travel to California or return to the state after traveling be tested for COVID within three to five days.
California Health and Human Services Secretary Dr. Mark Ghaly said the changes were prompted by what he called a 47% increase in COVID-19 case rates across the state since Thanksgiving. He said over that time, the statewide rate of daily new cases went from 9.6 per 100,000 residents to more than 14 per 100,000.
Ghaly said state officials also acted in hopes of avoiding the dramatic surge in cases experienced statewide last year during the winter holiday months.
"As we look at the evidence that masks do make a difference, even a 10% increase in indoor masking can reduce case transmission significantly," he said Monday.
California is exempting San Francisco from the rule. The city health department says San Francisco will continue to allow fully vaccinated people to remove their masks in gyms and workplaces. San Francisco has a high vaccination rate — nearly 90% of eligible residents have received at least one dose.
Under previous state guidelines -- which were followed by many counties including Riverside, Orange and San Diego -- masks were only required indoors at public transit facilities such as airports, healthcare settings, adult and senior care facilities, schools, correctional facilities, homeless shelters, emergency shelters and cooling centers.
The state technically already required mask-wearing for unvaccinated people at indoor public facilities, but the new rule will impact everyone regardless of vaccine status.
WATCH RELATED: Who's enforcing the statewide mask mandate that goes into effect Wednesday? (Dec. 14, 2021)