CDC Director Rochelle Walensky has signed off on updated versions of the Moderna and Pfizer-BioNTech vaccines that target the original virus and the omicron subvariants.

The new shots from Moderna and Pfizer-BioNTech target both the original strain of the coronavirus and the omicron BA.4/BA.5 subvariants that most people are catching now.

The vaccine maker alleges that its rivals Pfizer and BioNTech used some patented features of its mRNA technology to develop their COVID vaccines.

A committee of experts voted unanimously to recommend that the Food and Drug Administration authorize COVID-19 vaccines from Moderna and Pfizer-BioNTech for children as young as 6-months-old.

The company says this version targets both the original coronavirus and the beta variant, and appears to provide broader and longer-lasting protection against different strains, including omicron.

No deaths were reported in tests, and there were no signs of myocarditis, or heart inflammation, as a side effect.

Researchers in the U.K. have the first estimates for how long a third shot of the Pfizer vaccine will last. The findings are mixed.

Moderna said its current FDA-approved 50-microgram booster shot increased antibody levels against omicron 37-fold compared to pre-booster levels.

Moderna said its current FDA-approved 50-microgram booster shot increased antibody levels against omicron 37-fold compared to pre-booster levels.

Omicron has many more mutations than previous variants of concern, a fact that raises questions about how effective existing vaccines will be against the new form of the coronavirus.

Does a booster shot mean that you can go back to ... normal? Or is there still a newish kind of normal to face?

Moderna says the FDA is looking into reports of a rare side effect — myocarditis, or the inflammation of the heart muscle — in those who've gotten the shot.

The U.S. has pledged to deliver 1.1 billion doses of COVID vaccines to countries in need. Billions more are needed. NPR interviewed the State Department's global vaccine coordinator to learn more.

CDC Director Rochelle Walensky also endorsed a mix-and-match approach to boosters that would be flexible for patients and health care providers.

The Food and Drug Administration also gave an OK to boosters that differ from the vaccine originally used to immunize people against COVID-19. A mix-and-match approach could ease the booster rollout.