The Biden White House said earlier this month that beginning Sept. 20, booster shots would become available to all adults who were eight months past the date of their final vaccine. But that announcement was pending Food and Drug Administration and CDC advisers’ authorization. The Advisory Committee on Immunization Practices floated a more phased approach to boosters, starting with long-term health care residents and then essential front-line workers and older adults.

ACIP Chair Grace Lee said the committee would meet later to consider boosters for the rest of the general population but did not say when. A Pfizer-BioNTech representative told the working group the manufacturers would have data on their booster shots for all adults by the end of September at the earliest.

The committee’s COVID-19 vaccine working group insisted public health experts should focus on using booster doses to prevent severe disease in high-risk populations, and said preventing mild or asymptomatic disease may not be possible.