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.

Pfizer has submitted data on its bivalent COVID-19 booster shot that specifically targets the latest omicron subvariants. If authorized, the company says the shots could be ready as soon as September.

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.

Data show that a third dose can help boost kids' immunity. Some experts are skeptical that another shot is needed for younger kids.

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.

Pfizer and BioNTech are planning to ask the Food and Drug Administration to authorize a second COVID-19 booster shot for people age 65 and older.

"We believe additional information regarding the ongoing evaluation of a third dose should be considered as part of our decision-making for potential authorization," FDA officials said in a statement.

NPR has obtained the government's $5.3 billion contract for the first 10 million courses of Paxlovid, an antiviral pill for COVID-19. Here's what's in it.

Though people who are vaccinated and boosted appear to be better protected against omicron, the highly contagious variant has still led to breakthrough cases and a surge in infections worldwide.

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.

In a highly anticipated decision, the Food and Drug Administration authorized Pfizer's Paxlovid as the first antiviral pill to treat COVID-19 at home.

Vaccine and booster side effects can include fever, aches and fatigue. And this may be the first vaccine in history where people complain if they don't experience side effects, says one doctor.

In small studies in South Africa and in Germany, the results indicate a marked decrease in the ability of vaccines to neutralize this variant. But there are other findings that are encouraging.