BOSTON (CBS/AP) – The U.S. is expanding use of Pfizer’s COVID-19 vaccine to children as young as 12. The Food and Drug Administration said Monday the shot is safe and offers strong protection for younger teens based on testing of more than 2,000 U.S. volunteers.

Shots could begin soon once a federal vaccine panel issues recommendations for using the vaccine in 12- to 15-year-olds.

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Massachusetts said Monday it is awaiting further guidance, but is actively planning for the new group of people to be vaccinated.

“Individuals 12-15 can preregister now for vaccination by visiting and receive an email with booking instructions as soon as this expanded eligibility begins,” said Kate Reilly from the Massachusetts COVID-19 Command Center.

The CDC is expected to vote Wednesday on giving Pfizer the final go ahead.

Vaccinating children of all ages will be critical to a return to normalcy. Most vaccines rolling out worldwide have been authorized for adults.

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The latest news is welcome for U.S. families struggling to decide what activities are safe to resume when only the youngest family members remain unvaccinated.

WBZ-TV’s Dr. Mallika Marshall said she understands if some parents are reluctant to get their children vaccinated.

“You obviously want to do what is best for your kids, first do no harm. But I would also tell you I’m also very excited to get my children vaccinated,” said Dr. Marshall, who has children ages 12 and 13 years old.

“First of all it is not only good for them, it is good for their families, it will be good for the general public, because it will drive down infection rates and allow us to get back to normal. It will allow middle school students to get vaccinated before they start school in the fall.”

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