SUNNYVALE — The number of people being treated in California ICUs for coronavirus doubled overnight, Gov. Gavin Newsom said Saturday, as the deadly illness continues to spread in the state.

During a visit to South Bay fuel cell company Bloom Energy, which has shifted its operations to refurbishing ventilators to treat COVID-19 patients, Newsom said 410 people with the virus are now in ICUs across California, up from 200 on Friday.

The number of people hospitalized with coronavirus grew by nearly 40 percent, from 746 people Friday to 1,034 Saturday, Newsom said, with nearly 4,000 more patients who might have COVID-19 awaiting test results.

“I know there is a lot of appropriate attention on how many (confirmed cases) there are,” Newsom said. “We look less to those numbers, more to the hospitalization and ICU numbers to drive our policy.”

California has 7,345 ICU beds, of which 1,498 are in the Bay Area, according to a recent analysis by Kaiser Health News.

Newsom and San Jose Mayor Sam Liccardo spent Saturday afternoon visiting a Bloom Energy storage facility in Sunnyvale that has been converted in recent days to refurbish hundreds of ventilators from the state’s emergency cache, in hopes they can quickly be sent out for use in hospitals.

Governor @GavinNewsom tours the @Bloom_Energy warehouse where operations have shifted to fixing ventilators for Californians. #StayHomeSaveLives #COVID19 pic.twitter.com/bSBL3JJ9Qa — Office of the Governor of California (@CAgovernor) March 28, 2020

Health officials across the country have flagged the need for ventilators, which are a key tool in treating severe cases of COVID-19.

State officials have requested ventilators from a federal stockpile, Newsom said, but have not yet received any.

“We have our ask in and we are not waiting to see that fulfilled,” he said. “We are trying to repurpose what we have, and trying to find on the private market around the rest of the world those that we can source.”

Of the 10,000 ventilators California needs, Newsom said, the state has obtained 4,252, a figure that does not include those that hospitals already have on hand.

The state’s cache included 514 ventilators that Newsom said “had not been looked at and unboxed since 2011,” which was where Bloom Energy came in. The company has fully refurbished 80 of those ventilators, Newsom said, with another 120 set to be finished Saturday. The ventilators will then be distributed throughout the state.

Bloom Energy is among some 350 California businesses that have offered to retool their operations to help in the fight against the virus, Newsom said, including clothing companies that have switched to making masks and gowns, or distilleries making hand sanitizers.

“This is exactly the kind of spirit that defines the best of California, the best of the Valley, the best of the American spirit as well,” Newsom said.

Asked if California could soon see hospitals overwhelmed by a surge of coronavirus patients, Newsom said that could happen “if we go back to our normal routines without bending the curve” by following shelter in place orders meant to contain COVID-19.

Newsom has credited those measures with slowing the virus’ spread and giving the state time to expand its capacity for treating the sick, such as by setting up temporary field hospitals around California, including one in the Santa Clara Convention Center.

Still, he said, the rising number of people being treated at hospitals and in ICUs is concerning.

“If trends continue along those lines then we will start to manifest conditions that are very familiar to people on the East Coast,” Newsom said.