Quick Take:

A day after the U.S. Food and Drug Administration authorized offering booster shots of Pfizer’s COVID vaccine, California unveiled a plan to ramp up inoculation rates.

With millions of California residents slated to be eligible for a COVID-19 vaccine booster, the state is preparing to dramatically ramp up its inoculation rate to keep pace with the expected demand.

Officials unveiled a new COVID-19 Vaccine Action Plan on Thursday — the day after the U.S. Food and Drug Administration authorized offering a third Pfizer-BioNTech dose to those 65 and older, as well as younger people with underlying health conditions or who work in high-risk jobs.

“We are working hard to make sure not only are we prepared to provide it, but those who are eligible know that they’re eligible and know when the time is right,” California Health and Human Services Secretary Dr. Mark Ghaly said during a briefing.

For instance, officials say the state’s MyTurn platform will have the ability to screen residents’ booster eligibility, as well as send text messages to alert people of available options.

While specifics of the booster effort are still being worked out at the federal level, even a limited program would likely necessitate doling out millions of additional shots in a state the size of California.

State officials estimate there are about 6.6 million seniors statewide who eventually could be eligible for a booster dose, and Ghaly said many in this group were recipients of a Pfizer-BioNTech shot. Younger Californians would add their names to the queue depending on how high-risk conditions or settings are ultimately defined.

Moving expeditiously to cover these populations would entail dramatically accelerating the current inoculation rate.

At the peak of the rollout in April, providers statewide were giving out a bit more than 400,000 daily doses, on average. But over the past week, an average of only about 62,000 shots have gone into Californians’ arms per day, Times data show.

It’s been months since the state’s rolling average topped 100,000.

Officials say the slowdown is partially the byproduct of a strong share of the population — about 66% — having already been at least partially vaccinated for COVID-19, leaving a pool predominantly full of people who, for a number of reasons, have hesitated or resisted rolling up their sleeves.

Though the high-water mark is past, officials say there is existing infrastructure to reach that level again — though with the caveat that “this will require ongoing engagement of providers at every level to ensure they are ready, resourced and willing to operate at this capacity,” according to the vaccine plan.

Notably, the state’s assessment of the existing inoculation network “does not account for the additional capacity of mass vaccination clinics that many jurisdictions are planning to stand up.”

Mega-sites — such as those established at sports stadiums, universities and theme parks — were a hallmark of the early inoculation campaign.

But as demand fell, providers pivoted away from huge centralized operations in favor of a more community-based approach, bringing vaccines to where people live, work and recreate.

“California continues to lead the nation in both vaccines administered and low case rates. Vaccines work. They are safe, effective and are how we end this pandemic,” Gov. Gavin Newsom said in a statement. “We fully support our federal partners’ determination to provide boosters, and California has built the necessary infrastructure to mobilize such vaccine distribution.”

Ghaly, however, said the recent FDA decision is hardly the final step in the circuitous journey toward boosters.

Advisors to the Centers for Disease Control and Prevention opened a two-day meeting Wednesday to make their own, more specific recommendations about who should get the extra shots and when.

The Western States Scientific Safety Review Workgroup — which includes public health experts from California, Nevada, Oregon and Washington — also will need to weigh in.

“We’ve been working closely with our federal partners in preparation for additional guidance to Californians on the need for additional doses of vaccine to strengthen the protection we wrap around individuals, communities, schools, counties and the state as a whole,” Ghaly said.

But offering boosters — as well as the expansion of vaccine eligibility to children under 12, which is expected in the not-too-distant future — would move the inoculation campaign into a new phase at a critical time.

While California has made significant overall strides in its battle against the highly infectious Delta variant of the coronavirus, some experts and officials remain concerned about a potential resurgence later this year.

Areas with lower overall vaccine coverage also remain especially exposed to outbreaks — a reality that’s continuing to play out even as the current wave recedes.

Unvaccinated Californians are eight times more likely to be infected with COVID-19, 13 times more likely to be hospitalized and 15 times more likely to die from the disease than their vaccinated counterparts, Ghaly said.

In 11 of California’s 58 counties, more than 70% of the population has already been at least partially vaccinated, according to data compiled by The Times. However, 14 other counties have coverage rates below 50%.

Ensuring as many people as possible have the full benefit of vaccine protection, experts and officials say, will help break the cycle of surges the pandemic has wrought over the last year and a half.

And even with the upcoming emphasis on boosters, Ghaly said, “we’ll continue the strong drumbeat to get your first shot and start the series and get fully vaccinated.”

The Associated Press contributed to this report.

This story originally appeared in Los Angeles Times.