BOSTON (CBS) – Massachusetts is opening up COVID booster shots to any fully vaccinated resident age 18 or older, effective immediately, Governor Charlie Baker’s office said Thursday.

The state decided not to wait for guidance from the federal government, which could come as early as Friday. Some states and cities already allow all people ages 18 and up to get boosters of Pfizer’s vaccine.

“Effective immediately, all Massachusetts residents aged 18 and over are eligible to get a #COVID19MA booster 6 months after receiving the 2nd dose of the Pfizer or Moderna vaccines or 2 months since receiving a J&J single dose vaccine,” the state’s Office of Health and Human Services announced in a tweet.

“CDC recommendations allow for mixing and matching of different COVID-19 booster doses, and eligible individuals may choose which vaccine they receive as a booster dose. The Administration recommends that residents with questions about which booster is right for them should ask their health care provider for advice,” Baker’s office said in a statement.

Baker told reporters he was hearing there was a lot of confusion about who exactly who is eligible and when, and said this should clear things up.

“It’s one more piece of protection against COVID. As we head into the winter months, there’s always concern about people being indoors more than they’re outdoors,” Baker said. “If people have a concern about getting the booster, they should talk to their physicians. We’ve talked to the physicians in Massachusetts, and the vast majority of them think people should get a booster.”

Dr. Paul Sax, director of the infectious diseases clinic at Brigham & Women’s Hospital, said he is “strongly encouraging” people who are eligible to get one.

“It’s now clear that getting a third dose – I like to say third dose rather than booster – is really a good way of making the vaccines just as effective as they were the first month or so after you get them,” Sax said.

At a clinic in Danvers, the news spread quickly. “Actually I think it’s excellent. I wish it was done even sooner,” said Bob Hurley as he waited for his wife getting her shot.

“I’ll be seeing my parents who are older and more vulnerable,” said Lisa Core of Winchester, who got her booster Thursday. “I have young children who aren’t fully vaccinated, so I think the more protected we all are, the better, and healthier everyone else can be.”

The Food and Drug Administration is expected to approve Pfizer’s request to make its booster shot available to everyone 18 and over as early as Thursday.

The Centers for Disease Control and Prevention’s advisory committee is expected to take up the topic Friday afternoon. They will make the formal recommendation after the FDA’s expected authorization, and then CDC Dr. Rochelle Walensky will likely sign off on the plan.

Massachusetts residents can use vaxfinder.mass.gov to find a full list of locations to receive a booster.

For more information on the booster program, visit the state’s website.

CBSBoston.com Staff