SAN FRANCISCO (CBS SF) — State health officials have announced that parents will be allowed to sign up their 12-to-15-year-old children for a dose of Pfizer COVID-19 vaccine starting Thursday morning.

The expanded eligibility announced late Wednesday night comes after the Centers for Disease Control and Prevention’s vaccine safety review panel and the Western States Scientific Safety Review Workgroup recommended that the vaccine is safe and effective in protecting 12-to-15-year-olds against severe illness, hospitalization and death.

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Signups for the shots can be made on the statewide booking system or by calling California’s COVID-19 Hotline at 1-833-422-4255.

In Santa Clara County, parents can sign their children up at vax.sccgov.org

“This is fantastic news,” said Dr. Sara Cody, health officer and director of public health for the County of Santa Clara. “The Pfizer vaccine is safe and effective, and I’m thrilled that more of our young people can now get vaccinated to protect themselves, protect their community, and safely return to more activities.”

In San Mateo County, parents can schedule an appointment through the state’s MyTurn.ca.gov system or drive up and register on site. Vaccinations are available at the San Mateo County Event Center, 1346 Saratoga Drive, San Mateo, this week and next.

San Mateo County Health’s Srija Srinivasan said the county also plans to work with school districts and San Mateo County Superintendent of Schools Nancy Magee to get eligible teenagers vaccinate

There are already two regular vaccination clinics on school campuses: one at Cesar Chavez Ravenswood Middle School in East Palo Alto and one at San Mateo High School in San Mateo.

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“We want to keep learning as to what are the best ways to reach young people and their families,” Srinivasan said. We hope the 12 to 15 youngsters and the 16- and 17-year-olds can also help promote vaccines to other family members and are looking forward to reaching even more people as we have more eligible.”

Gov. Gavin Newsom called the announcement a major step in the state’s battle to control the pandemic.

“The more Californians who are able to get vaccinated, the better we can protect our communities and slow the spread of COVID-19,” Newsom said in a news release. “Our efforts to protect the health and wellbeing of Californians are paying off, as we’re now leading the country with over 32 million vaccines administered and some of the lowest positivity rates in the entire country. Having vaccines expanded to teenagers is the next step in California’s path to safely reopening next month.”

The new order makes an additional 2.1 million Californians eligible for vaccination.

“California is ready to safely deliver vaccines to young people aged 12 and up,” said State Epidemiologist Dr. Erica Pan. “We have streamlined the enrollment process to include more clinics and providers that can administer vaccines to this next age group where they can also catch up on other vaccines that may have been missed over the course of this pandemic.”

The Pfizer vaccine is administered in two doses taken three weeks — 21 days — apart. It has already been safely administered to millions of California adults, including more than 30 percent of 16- and 17-year-olds.

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Pfizer was the first vaccine manufacturer to submit clinical trial data on the 12-15 age group to the FDA for authorization. Moderna is expected to submit trial data for the same authorization in the coming months. Johnson & Johnson is currently conducting clinical trials for the 12-17 age group.