CALIFORNIA — Gov. Gavin Newsom on Friday announced the activation of the California National Guard to support local communities with additional testing facilities and capacity amid the national surge in COVID-19 cases driven by the Omicron variant.

More than 200 Cal Guard members were set to be deployed across 50 Optum Serve sites around the state, serving as temporary clinical staff while permanent staff is hired, the governor announced.

The difficulty finding coronavirus test kits in many parts of California and delays in getting results are causing increasing frustration and contributing to the surge of infections that in just two weeks more than doubled the number of people in hospitals with COVID-19.

The omicron variant has spread rapidly around the nation and accounted for at least 80 percent of COVID-19 cases in California, according to Newsom. Negative test results can be a necessity for any number of activities, from going to work to boarding an airplane or attending a sporting event. Delays in getting results — or inability to find a test kit — can mean people with very mild or no symptoms may presume they are not infected and go about their usual routines.

“We have robust testing in California, we always want more, we’re seeking to get more, but that testing is a key part of keeping Californians knowledgeable about who’s infected, who’s exposed and helping us keep transmission in a more manageable place,” said Dr. Mark Ghaly, the state’s health secretary, at a news briefing on Wednesday.

Newsom’s announcement comes as Omicron continues to spread rapidly across the globe, accounting for at least 80 percent of COVID-19 cases in California.

“California has led the country’s fight against COVID-19, implementing first-in-the-nation public health measures that have helped save tens of thousands of lives,” Newsom said. “We continue to support communities in their response to COVID by bolstering testing capacity.”

The state has about 6,000 testing sites which have expanded hours amid the extreme demand for testing.

On Friday, the state’s testing positivity rate was 21.7 percent, up from 2.2 percent the same time last month.

“Californians are managing through a significant number of reported cases on a daily basis,” said Ghaly said.

He added that the state is better prepared to handle this particular surge, compared with last winter’s devastating winter with COVID-19.

The steep increase in cases prompted officials this week to extend the state’s indoor mask mandate for yet another month.

Along with the renewed mandate, Californians will also be urged to make sure they are equipped with a well-fitted mask or one with a filtration system such as an N95 mask.

“Masks that were really helpful in the beginning are not as helpful today,” Ghaly said.

The renewed order was set to remain in place until Jan. 15, but Dr. Mark Ghaly, the state’s health secretary, announced that it would be extended until Feb. 17.

“At that time, we will again reevaluate the conditions across California and our communities in our health care delivery to make sure that we are taking the latest information into account to determine if there there would be another extension, or if we’re prepared to lift that requirement,” Ghaly told reporters on Wednesday.

The Associated Press contributed to this report.