An advisory panel for the U.S. Food and Drug Administration (FDA) endorsed on Friday a booster dose of the Pfizer-BioNTech COVID-19 vaccine six months after full vaccination in people 65 and older and for individuals at high risk for severe disease.

The decision came after members of the FDA's Vaccines and Related Biological Products Advisory Committee voted against advising the agency to approve boosters for anyone 16 and older after hours of debate.

Members of the committee expressed doubts about the safety of a booster dose in younger adults and teens, and said they wanted to see more data about the safety and long term efficacy of a booster dose.