In this March 16, 2020, file photo, Tomas Aragon, the health officer for the city and county of San Francisco, speaks during a news conference in San Jose, Calif. In a letter to health providers dated Tuesday, Nov. 9. 2021, Aragon, now the State Public Health Officer, told providers they should "not turn a patient away who requesting a booster" if they are age 18 and up and it has been six months since they had their second Moderna or Pfizer vaccine or two months since their single Johnson & Johnson shot. Credit: Dai Sugano/Bay Area News Group, File

California is among three U.S. states now allowing coronavirus booster shots for all adults even though federal health officials recommend limiting doses to those considered most at risk.

The nation's most populous state, along with Colorado and New Mexico, instituted their policies to try to head off a feared surge around the end-of-year holidays when more people are gathering inside.

Colorado and New Mexico have among the nation's highest rates of new infections, while California—lowest in the nation earlier this fall—now joins them in the "high" tier for transmission, according to the Centers for Disease Control and Prevention.

New Mexico Gov. Michelle Lujan Grisham signed an executive order Friday expanding eligibility for COVID-19 booster shots. Her state health department's acting secretary, Dr. David Scrase, said rising case numbers have some hospitals in New Mexico overwhelmed.

"COVID-19 is incredibly opportunistic and it's our job to ensure that the virus has fewer and fewer opportunities to spread," Scrase said. "If it's time for you to get a booster, please do so right away."

President Joe Biden's administration had sought approval for boosters for all adults, but U.S. Food and Drug Administration advisers in September decided it isn't clear that young healthy people need another dose. They instead recommended boosters only for those over 65 and with certain underlying or whose jobs are high risk for the virus.

Colorado Gov. Jared Polis speaks during a news conference about Colorado offering coronavirus vaccinations to children, Thursday, Oct. 28, 2021, in Denver. Infection rates have soared in Colorado over the past month, and Polis signed an executive order on Thursday, Nov. 11, 2021, to expand the use of booster shots to quell the recent surge in COVID-19 infections. Credit: AP Photo/David Zalubowski, File

In California, state Public Health Officer Tomás Aragón sent a letter to local health officials and providers saying they should "allow patients to self-determine their risk of exposure."

"Do not turn a patient away who is requesting a booster" if they are age 18 and up and it has been six months since they had their second Moderna or Pfizer vaccine or two months since their single Johnson & Johnson shot, he wrote.

He told pharmacies to prioritize boosters to those in skilled nursing or assisted living facilities due to waning immunity from the earlier shots. But generally, providers "should not miss any opportunity" to give vaccines to the unvaccinated or boosters to everyone else anytime they visit a drug store, hospital or medical office.

Many states are now experiencing rising cases and more hospitalizations. Nationwide in the last week there were about 73,000 new cases daily, roughly 10,000 more than three weeks ago.

California Gov. Gavin Newsom, left, receives a Moderna COVID-19 vaccine booster shot from California Health and Human Services Secretary Dr. Mark Ghaly at Asian Health Services in Oakland, Calif., Wednesday, Oct. 27, 2021. In a letter to health providers dated Tuesday, Nov. 9. 2021, Dr. Tomas Aragon, the State Public Health Officer, told providers they should "not turn a patient away who requesting a booster" if they are age 18 and up and it has been six months since they had their second Moderna or Pfizer vaccine or two months since their single Johnson & Johnson shot. Credit: AP Photo/Jeff Chiu, File

In Colorado, where some hospitals are stretched to the breaking point, Gov. Jared Polis signed an executive order on Thursday to expand use of booster shots. A day later he had a dire warning for the roughly 20% of eligible people in his state who have yet to get a single dose.

"We wouldn't even be here talking about this if everyone was vaccinated," the Democratic governor said at a news conference. "If you are not vaccinated, you're going to get COVID. Maybe this year, maybe next year."

Officials in Colorado, California and New Mexico said they have ample supplies of vaccines to provide initial vaccinations and boosters to all who want them.

White House press secretary Jen Psaki on Friday said the Biden administration continues to advise health leaders across the country "to abide by public health guidelines coming from the federal government."

  • Nurse Mary Ezzat prepares to administer a Pfizer COVID-19 booster shot to Jessica M., Thursday, Aug. 19, 2021, at UCI Medical Center in Orange, Calif. Jessica M. is a healthcare worker who is also immunocompromised. California Gov. Gavin Newsom, along with Colorado Gov. Jared Polis and New Mexico Gov. Michelle Lujan Grisham have taken steps to expand the use of booster shots to quell the recent surge in COVID-19 infections. Credit: Jeff Gritchen/The Orange County Register via AP

  • A patient waits to be called for a COVID-19 vaccination booster shot outside a pharmacy in a grocery store, Wednesday, Nov. 3, 2021, in downtown Denver. Infection rates have soared in Colorado over the past month, and Gov. Jared Polis signed an executive order on Thursday, Nov. 11, 2021, to expand the use of booster shots to quell the recent surge in COVID-19 infections. Credit: AP Photo/David Zalubowski, File

California Health and Human Services Secretary Dr. Mark Ghaly earlier in the week said California's decision doesn't conflict with federal guidelines. The Centers for Disease Control and Prevention was "very clear that they had two categories—groups that should get a booster and groups that may." he said.

"We know that a number of Californians work in crowded public settings," Ghaly said. "Because of your work-related risk or even you live with people who have underlying conditions (and) are at higher risk themselves, or you're a member of a community that's been ravished and hard-hit by COVID ... it's permissive by the CDC and the FDA to go ahead and get the ."

Dr. Kirsten Bibbins-Domingo, a professor of epidemiology at University of California, San Francisco, said boosters have lagged. That's worrisome as winter approaches and the highly contagious delta variant, which caused a summer spike, continues to circulate.

The delta variant is "really good at finding people, including people who got vaccinated at the beginning of the year and now that vaccination is wearing off a little bit," she said. "Delta is a powerful force and everybody needs that third dose."