An additional four cases of the Omicron variant were reported in San Diego County Wednesday, the same day the state reinstated an indoor mask mandate for Californians 2 and older, regardless of their vaccination status.
The two previously reported cases of the variant involved fully-vaccinated patients who had received their booster shots, while the four omicron patients reported Wednesday were fully vaccinated but had not received booster shots, according to county records.
The Delta variant still remains the predominant variant of concern, county health officials said.
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"The holidays and colder temperatures mean San Diegans are spending more time indoors, where COVID-19 spreads more easily," said Dr. Wilma J. Wooten, county public health officer. "I urge our community to continue taking the recommended precautions so that we can all have a safe and happy holiday season."
In light of a statewide increase in cases and hospitalizations, and the spread of the Omicron variant, the California Department of Public Health implemented a renewed mask mandate Wednesday. It will remain in place until Jan. 15.
The state also toughened 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 if it's a PCR test. The previous rules required a test within 72 hours of the event.
State officials will also recommend, but did not require, that people who travel to California or return to the state after traveling be tested for COVID within three to five days.
Among the indoor public spaces affected by the mask mandate will be retail stores, restaurants, theaters, family entertainment centers and government offices that serve the public.
The San Diego County Health and Human Services Agency reported 646 new COVID-19 infections and two deaths Wednesday, increasing the cumulative totals to 395,723 cases and 4,395 deaths.
As of Wednesday, more than 5.89 million doses of the three vaccines now available have been administered throughout the region.
More than 2.72 million San Diego County residents have received at least one dose of a COVID-19 vaccine, around 86.5% of all eligible residents. More than 2.42 million San Diegans, or 76.9% of eligible residents, are fully vaccinated against COVID-19. In addition, 601,951 booster shots have been administered in the region.
The number of coronavirus patients in San Diego County hospitals increased by five people to 359, according to Wednesday's data. Of those patients, 94 were in intensive care, one fewer than Tuesday.
A total of 21,767 new tests were reported to the county on Wednesday. A total of 3.4% of all tests returned positive over the past two weeks.