Citing a sharp increase in COVID-19 infection rates since Thanksgiving, the state announced Monday that beginning Wednesday, mask-wearing will become mandatory in all indoor public settings across California regardless of vaccination status.
The mask mandate, mirroring a requirement already in effect in Los Angeles County and select other counties across the state, will remain in place until Jan. 15.
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 current rules require 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.
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California Health and Human Services Secretary Dr. Mark Ghaly said the rule change is being 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.
Under current state guidelines -- which are followed by many counties including Riverside, Orange and San Diego -- masks are 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 already technically requires mask-wearing for unvaccinated people at indoor public facilities, but the new rule will impact everyone regardless of vaccine status.
Los Angeles County has long maintained a mask-wearing mandate at indoor public facilities. Ghaly said roughly half of California's population lives in counties that already have an indoor mask-wearing requirement in place.
Among the indoor public spaces affected are retail stores, restaurants, theaters, family entertainment centers and government offices that serve the public.