Kaiser Permanente Martinez Medical Offices is one of the many locations hosting COVID-19 testing and vaccination sites around Contra Costa County, located at 200 Muir Road in Martinez, Calif. on January 13, 2021. (Samantha Laurey/Bay City News)

After hearing frustration from the Contra Costa County Board of Supervisors last week about not cracking down on businesses ignoring COVID-19 mandates, Contra Costa Health Services director Anna Roth told the board Tuesday that 12 of the 13 businesses previously flaunting rules are now complying.

“All but one are currently in compliance, and we’re following up with that one,” Roth said.

That’s good news for health officials this week. The bad news is that the predicted winter surge has arrived, as hospitalizations and infections are trending back up since Thanksgiving.

“Currently we have 1,458 active COVID cases in our county; this is an increase of nearly 19 percent in the last two weeks,” Roth said. “Our test positivity rate rose at the end of November but is now relatively steady at 2.3 percent.”

Hospitalizations, which were trending downward for weeks, are back up slightly — 36 from 33 — since last week. Statewide cases have gone up 47 percent since Thanksgiving, with hospitalizations up 14 percent.

Just over 76 percent of county residents are now fully vaccinated, which would’ve had the county closer to dropping indoor mask mandates, if not for the new statewide mandate going back into effect Wednesday.

“California is now starting to experience a winter surge in COVID-19 cases,” Roth said.

The news was mixed for new variant Omicron, Roth said. Though no cases have officially been reported, as in other Bay Area counties, it has been detected in county wastewater samples.

“We are assuming that we will be seeing cases come soon,” Roth said.

Of the newest demographic to receive vaccines, 22 percent of the county’s 5- to 11-year-olds are fully vaccinated, with 38 percent having at least one dose. Twenty-five percent of the county has received booster shots.

County health officer Dr. Chris Farnitano said the county is still waiting to hear from the state on indoor mask exceptions, but he expects masks to be required indoors until at least Jan. 15.

He said Omicron is more contagious that previous strains, and those avoiding vaccines believing they have natural immunity should think again. Two doses will offer some protection, but Omicron has made boosters necessary.

“If natural immunity was your reason for not getting vaccinated before, that rationale no longer exists,” Farnitano said. “You are not protected from Omicron.”