SACRAMENTO (CBS13/AP) — With Omicron cases surging, a new COVID-19 vaccine mandate was ordered in California by Gov. Gavin Newsom requiring all healthcare workers to get a booster shot.

“With Omicron on the rise, we’re taking immediate actions to protect Californians and ensure our hospitals are prepared,” Newsom tweet Tuesday.

READ MORE: Smoking Solution? California Bill Would Eliminate Litter Left Behind By Smokers

Newsom said an official announcement with more details on this mandate will come Wednesday.

The state’s roughly 2.2 million health care workers were previously mandated to be fully vaccinated by the end of September.

Meanwhile, on Tuesday, President Biden announced the government would make 500 million rapid at-home tests freely available to Americans, increase support for hospitals and add testing sites in regions that need additional capacity, CBS News reported.

On Monday, the CDC released new data showing that the omicron variant is now making up more than 73 percent of new infections. It has been labeled the most common COVID-19 variant within the United States.

READ MORE: Elk Grove Horse Rescue Robbed Over The Weekend

Concerns stem from the rise of omicron, which as of Monday was the dominant variant of the coronavirus in the United States. Areas in the Midwest and Northeast are seeing the biggest jump in cases and hospitalizations amid frigid temperatures that have kept people indoors.

Much about the variant remains unknown, including whether it causes more or less severe illness. Scientists say omicron spreads more easily than other coronavirus strains, including delta. Early studies suggest the vaccinated will need a third shot for the best chance at preventing infection but even without the extra dose, vaccination still should offer strong protection against severe illness and death.

California has so far fared far better than many other states. The U.S. Centers for Disease Control and Prevention lists California as a place with “high” transmission of the virus, along with nearly everywhere else in the country. But in the last week California averaged 114 new cases per 100,000 people, less than half the national rate.

While 70% of Californians have been fully vaccinated, that still leaves 30% — or roughly 12 million people — who haven’t been. The California Department of Public Health says people who are not vaccinated are seven times more likely to get infected, nearly 13 times more likely to be hospitalized and nearly 16 times more likely to die from the coronavirus.

Coronavirus related hospitalizations have been rising slowly in California, up 15% in the last 11 days to 3,852. That’s less than half as many as during the late summer peak and one-fifth of a year ago, before vaccines were widely available.

MORE NEWS: Homeless Shelter Proposed Next To Children’s Receiving Home Of Sacramento

But while hospitals overall have fewer patients than last winter, many have fewer workers to treat the patients they do have. The staffing shortage comes as businesses are having trouble finding workers, including hospitals. A recent study by the University of California-San Francisco estimated the state’s nursing shortage could persist until 2026.