(Bloomberg) -- Covid-19 boosters formulated to protect against newer strains of the virus should become available in the US within days after the Centers for Disease Control and Prevention signed off on their rollout Tuesday.

CDC Director Mandy Cohen endorsed the use of the new shots following recommendation by a panel of vaccine and health experts for the booster shots from Moderna Inc. and from Pfizer Inc. and BioNTech SE. The panel voted 13-1 to recommend its use in those six months and older.

 “CDC recommends everyone 6 months and older get an updated Covid-19 vaccine to protect against the potentially serious outcomes of Covid-19 illness this fall and winter,” the agency said in an emailed statement. “Updated Covid-19 vaccines from Pfizer-BioNTech and Moderna will be available later this week.” 

Cohen’s final green light means the shots can be administered across the US. The Food and Drug Administration has already approved them.

Distribution of these boosters could be especially helpful for Pfizer, which has struggled amid a sharp decline in sales of its Covid vaccine and antivirals after a surge during the pandemic. The company is waiting to see how purchases of both products perform this quarter before deciding on cost-cutting measures.

Read More: Moderna’s Covid Vaccine Helps With New Strain, Study Shows

The BA.2.86 strain, known as Pirola, and EG.5 variant, dubbed Eris, are gaining ground. Hospitalizations are also rising for the first time this year, though they are still less frequent than in previous waves.

In June, US health officials told drugmakers to reformulate their boosters in time for the fall season that would protect against another subvariant, the XBB.1.5, that accounted for some 40% of infections at the time. But the new Eris strain has since become the most widely circulating variant, and the highly mutated Pirola is also spreading, raising questions about how effective the new boosters will be.

Moderna said earlier this month that its booster increased antibodies to Pirola almost ninefold in a human clinical trial. Pfizer said its vaccine elicited a “strong neutralizing antibody response” to the same strain in a pre-clinical study. Both companies said trials showed their products also offered some protection against Eris.

Those early findings, and others showing that antibodies from prior infection and vaccination still offer protection against Pirola, are reassuring, the CDC said Friday.

Members of the advisory panel said they endorsed a universal recommendation to allow for broad access to the shot. A couple raised questions about a lack of data on children for this particular booster, while others said the public needs to be informed about the increased risk for certain ages and populations. 

Beth Bell, a clinical professor at the School of Public Health at the University of Washington in Seattle, said there needs to be messaging that clarifies that some individuals are at a much higher risk. “A lot of people with underlying medical conditions and who are older, are dying, and they really need to get a booster,” she said.  

Pfizer executives participating in Tuesday’s CDC advisory panel said they plan on charging $120 per booster, while Moderna plans to charge $129. A Covid booster by Novavax Inc is currently under review with the FDA for those 12 and up, according to a statement from the company. If it’s approved by FDA it would likely fall under the CDC panel recommendation automatically and not need a separate vote.

(Updates headline and first three paragraphs to add CDC director endorsing new shot.)

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