It’s been a big day for COVID boosters —

By Tuesday afternoon, both the Food and Drug Administration and the Centers for Disease Control and Prevention had cleared a new round of Moderna or Pfizer-BioNTech COVID-19 boosters for Americans ages 50 and older, CBS News reports.

The CDC’s sign-off followed the FDA’s.

And not only did the CDC okay a second booster for older Americans, it also authorized a fourth shot for all adults who received the Johnson & Johnson vaccine and booster at least four months ago, per The Washington Post.

Data released by the CDC shortly before the decision to authorize the second booster showed those who received the single-shot J&J regimen to be at a greater risk of serious hospitalization and illness than those who received the mRNA vaccines, reports the Post. The CDC strongly recommends those populations consider getting a booster dose of either the Pfizer or Moderna vaccine, per The Hill. 

The second booster is “especially important for those 65 and older and those 50 and older with underlying medical conditions that increase their risk for severe disease from COVID-19 as they are the most likely to benefit from receiving an additional booster dose at this time,” said CDC Director Rochelle Walensky, per The Wall Street Journal.

The FDA and CDC also authorized a second Pfizer booster for immunocompromised individuals ages 12 and up who’ve received their first COVID booster, and a second Moderna booster for immunocompromised people ages 18 and above, the Journal notes.

The agencies’ decisions arrive as as the Omicron subvariant BA.2 continues to gain ground in the U.S.