The number of available intensive care unit beds in California’s San Joaquin Valley plummeted to zero for the first time Saturday, state officials announced as ICU units fill up statewide amid spiking COVID-19 cases.

Just a day earlier, the region’s ICU capacity was at 4.5%, according to the California Department of Public Health.

The region comprised of 12 counties in central California, along with the enormous Southern California region, contain more than 60% of the state’s 40 million residents. Last week, the two regions were ordered to follow the strictest anti-COVID-19 rules under a new state stay-at-home order that aims to keep hospitals from being overwhelmed by restricting infectious contacts.

The 0% calculated by the state doesn’t mean all hospitals have run out of intensive care unit beds, and in Stanislaus County 3.6% of ICU beds were available as of Saturday, said Kamlesh Kaur, a spokeswoman for the county’s public health department.

“From what we understand, the state is looking at the percentage of available, staffed ICU beds and makes adjustments based on the percentage of COVID-positive patients admitted to hospitals,” Kaur said.

She said the county has activated a surge plan, which allows hospitals to transfer non-COVID-19 patients to a facility opened by the state in Sacramento to provide relief for local hospital workers. At least one local hospital has requested and received help from volunteer medical workers, she said.

In Imperial County, El Centro Regional Medical Center recently opened a tent in its parking lot with capacity for 50 non-coronavirus patients as it deals with the crush of people with COVID-19.

Meanwhile, the state is awaiting the first batch of Pfizer’s coronavirus vaccine and plans to distribute it to hospitals to inoculate healthcare workers on the front lines of the pandemic.

Gov. Gavin Newsom tweeted that a group of medical experts convened by Western states met Saturday to discuss the vaccine. He added that he expects the distribution of the vaccine to begin as early as Sunday.

Public health officials blame the surge in cases on people ignoring safety rules to wear masks and social distance except for people in their own households. They have voiced fears that COVID-19 infection rates and hospitalizations will continue to soar as people ignore stay-at-home orders to gather for the holidays.

The restrictions — the toughest since a spring lockdown — have been met with defiance from some business owners who say it will ruin them after nearly a year of seeing their clientele avoid public places because of COVID-19 fears and on-again, off-again restrictions.

Six counties in the San Francisco Bay Area and the city of Berkeley chose to implement their own voluntary orders independent of the state. Sonoma County joined that group Thursday, implementing its own lockdown beginning Saturday.

San Francisco reported 323 new cases on Saturday, the highest since the pandemic began.