CDC advisers try to work out the details on booster shots

With booster doses of Pfizer’s COVID-19 vaccine now authorized in the U.S., government advisers reconvened on Thursday to tackle the most contentious question yet: Exactly who should roll up their sleeves right away?

Late Wednesday, the Food and Drug Administration signed off on extra shots of the Pfizer formula for a broad swath of Americans: those 65 and older, people at high risk of severe illness, and health care workers and others in danger of becoming infected on the job.

But that was not the last hurdle. The Centers for Disease Control and Prevention sets final U.S. policy on who qualifies for the extra shot. And the CDC’s advisers were set to vote Thursday on how many of the roughly 26 million Americans who had their last Pfizer shot at least six months ago should go ahead and get that third dose.

The widespread dispensing of the boosters would represent an important new phase in the nation's vaccination drive. Britain and Israel are already rolling out a third round of shots over strong objections from the World Health Organization that poor countries don't have enough for their initial doses.

Whatever the decision from the CDC, millions more Americans still will face confusion -- those who received Moderna or Johnson & Johnson shots early in the vaccine rollout. The government still hasn’t considered boosters for those brands and has no data on whether it’s safe or effective to mix-and-match and give those people a Pfizer shot.

The priority still is to vaccinate the unvaccinated. About 182 million Americans, or 55% of the population, are fully vaccinated.

The COVID-19 vaccines used in the U.S. still offer strong protection against severe illness, hospitalization and death, but immunity against milder infection appears to be waning months after people’s...