California will require health care workers to get COVID-19 booster shots, Gov. Gavin Newsom announced Tuesday.

Driving the news: He's taking the step to "protect Californians during a potential winter surge," per a statement from Newsom's office. "With Omicron on the rise, we're taking immediate actions to protect Californians and ensure our hospitals are prepared," Newsom tweeted.

The big picture: The most populous state already has a coronavirus vaccine mandate for health care workers and other personnel.

• But officials have stepped up measures in response to the surge of the Omicron variant — which accounted for more than 73% of recent COVID-19 cases in the U.S. this week.
• The state has also reinstated a mask mandate in all indoor public spaces.

What's next: Newsom's office said details of the booster shot mandate would be announced Wednesday.

Editor's note: This article has been updated with new details throughout.