FDA authorizes additional Moderna, J&J shots, broadening booster rollout

Millions more Americans are now eligible for a booster dose of a coronavirus vaccine, with the Food and Drug Administration announcing Wednesday evening expanded authorizations for both Moderna's and Johnson and Johnson's shots.

The decision to clear an additional dose of both vaccines comes one month after the regulator did the same for Pfizer and BioNTech's shot and reflects concern that the strong protection they produce may be waning, particularly among vulnerable groups.