The announcement, which was prompted by pressure from the Trump administration, was met with confusion, including from those who said they have been unable to find out how to set up an appointment to receive vaccine. Some county websites, which people access for vaccine guidance and appointment registrations, continued to advise that only healthcare workers and residents in long-term care settings qualify for the vaccine.

On Wednesday, Gov. Gavin Newsom announced a new system to let people know when they are eligible to receive a vaccine, but there were no additional details other than it is expected to launch next week. In addition, the governor’s office said a “second phase” of that system will help counties, cities and providers run mass vaccination events and allow the public to schedule vaccination appointments for those events. No timeline was given on when that second phase will be available.

“There is no higher priority than efficiently and equitably distributing these vaccines as quickly as possible to those who face the gravest consequences,” Newsom said in a statement on Wednesday. “Individuals 65 and older are now the next group eligible to start receiving vaccines. To those not yet eligible for vaccines, your turn is coming. We are doing everything we can to bring more vaccine into the state.”

California officials have struggled thus far to distribute its allotment of vaccine doses. As of Monday, California had received more than 2.4 million doses of vaccine, but less than one-third had been administered. There has been lower than expected demand from the healthcare and nursing home workers who have highest priority to receive the vaccines, with up to 40% declining the initial opportunity to be vaccinated.

In response, state officials expanded access last week to all healthcare workers and relaxed guidelines for unused doses.

Newsom last week set an ambitious target of vaccinating an additional 1 million people over the course of 10 days ending Jan. 17. The state announced several mass vaccination sites in the state to help doll out doses.

More than 10,000 people signed up for vaccinations at the Disneyland site in less than two hours on Tuesday. Orange County set a goal to vaccinate more than 7,000 people per day at the superpod site.

“While we still face difficult months ahead, with these vaccines—with more coming online in the near future—we will triumph and overcome the biggest challenge of our generation,” said Board of Supervisors Chairman Andrew Do said.

In all, the state added more than 6 million people to the list of those who qualify by extending vaccine eligibility to those 65 and older.

Ahead of the state announcement in Los Angeles County, pop-up messages were added to the vaccine registration site warning people not to make appointments unless they were eligible to do so. As of last week, L.A. County had received more than 490,990 vaccine doses, administering over 145,620 first doses and more than 6,150 second doses.

California’s massive surge in COVID-19 cases has focused attention on the state’s handling of vaccine supplies. Los Angeles County is nearing 1 million confirmed coronavirus cases, meaning 1 out of every 10 in the county has been infected at some point during the pandemic. Statewide, more than 2.7 million Californians have tested positive.

Federal officials said the decision to open up eligibility was an attempt to get states to take swifter action. U.S. Health and Human Services Secretary Alex Azar said Tuesday that states had simply moved too slowly and that lifesaving vaccine should be doled out immediately.

“That is the most effective way to save lives now,” Azar said, “and some states’ heavy-handed micromanagement of this process has stood in the way of vaccine reaching a broader swath of the vulnerable population more quickly.”

The federal guidelines call for anyone 65 and older to qualify now for the Pfizer-BioNTech and Moderna vaccines. In addition, the federal guidelines say anyone 16 to 64 years old with a documented medical condition should also qualify now.

Azar said state regulations limiting who was eligible had “obstructed speed and accessibility” of the vaccines.

To push states into making vaccines more readily available, Azar said the federal government was providing two weeks’ notice that future doses would be released to states based on how effectively each used its existing supplies.

“It gives states a strong incentive to ensure doses are going to work protecting people, rather than sitting on shelves or in freezers,” Azar said. “With the case counts we face now, there is absolutely no time to waste.”

The federal push appears to have prompted state officials to reconsider their plans. Previously, the state planned to allow individuals in certain job sectors, such as education and agriculture, along with adults 75 and older, to be vaccinated next, followed by individuals 65 to 74. Under the new guidelines, the state lowers the age threshold to 65 years and older, bumping that group up to priority access.

The state, however, would wait until the next tier to allow individuals 16 to 65 with medical conditions to be eligible for the vaccine.

The state’s restrictions on who qualifies for the vaccine and when were intended to ensure the limited supply was properly prioritized and that people could not buy their way to the front of the line. Newsom announced last week that the state would ease restrictions to ensure that vaccine could be offered to those in other lower-tier groups, such as teachers, child-care workers and people over the age of 75, if there was a risk of the vaccine expiring.

Wednesday’s eligibility expansion poses significant challenges. California counties are scrambling to find more healthcare professionals who can administer the shots, large facilities where inoculations can be offered, and more of the vaccines themselves.

In Santa Clara County, officials say they have been so successful at distribution of the vaccine that they need more doses. The county asked the state for 100,000 more vaccine doses but was told this week it would receive 6,000, said Dr. Jeff Smith, county executive. That will affect the county’s goal, starting next week, of 35,000 weekly vaccinations, he said.

The shifting pool of who is eligible has complicated the county’s plans on how to distribute the vaccines.

“We’re getting confusing and inconsistent messaging,” Smith said.

Some members of the state’s vaccine advisory committee expressed concern in a meeting Tuesday that, with the focus on age, individuals who might face other vulnerabilities could be lost in the shuffle. Others have raised concern that at-risk individuals, including essential workers, could be overlooked as the doors open for a wider pool of eligible vaccine recipients.

“When you add this big group of people, you end up with not enough vaccine,” Carol Green of the California State Parent Teachers Assn. said at the meeting.

Times staff writer Taryn Luna contributed to this report.