Sep 1, 2022 - Health

What to know about new COVID boosters

Illustration of a virus cell surrounded by question marks

Illustration: Aïda Amer/Axios

The first updated COVID-19 boosters are days away from going into the arms of Americans. But the expedited way in which they're being rolled out, and unknowns on how well they'll work, have left many people leery and full of questions.

Why it matters: Experts generally agree COVID vaccinations were in need of an update to target strains like Omicron that now account for the majority of U.S. cases. And the evidence suggests the reformulated Pfizer-BioNTech and Moderna shots should protect those at greatest risk from hospitalization and death.

With a CDC vaccine advisory panel set to meet today to consider recommending the shots, Axios checked in with leading public health experts to suss out the biggest lingering questions:

Should we get Covid boosters right away?

  • It depends. People who haven't been vaccinated should get the original shots first, said Andrew Pekosz, co-director of the Johns Hopkins Center of Excellence for Influenza Research and Surveillance. The boosters were designed to be used as a boost only with a lower dose of mRNA.
  • The consensus for people who already got a booster or caught COVID this summer is to wait at least 60 days before getting these shots, Megan Ranney, academic dean at the Brown University School of Public Health, wrote on Twitter.
  • For still others, it's a personal choice partly based on what could lie ahead. Some people could reasonably hold off until closer to October or November, to maximize protection ahead of an expected surge during the holidays. That might also buy a little time to see how well the shots are working.

Why were the new shots authorized without real-world data on how they work in humans?

  • The Biden administration is putting speed ahead of having all the data on how the vaccines work in order to target the dominant strain.
  • It's largely like the process for making a seasonal flu vaccine, in which an established vaccine technology gets reformulated to target the strain experts believe is likeliest to be circulating.
  • "If you know the vaccine platform works, just putting a new variant sequence into it shouldn't necessitate you do a full-blown clinical trial once you have all that data," Pekosz said.
  • The real-world data gets collected and studied after people start getting these shots, Ranney said. Definitive clinical data will be available from manufacturers in one to two months, per Peter Marks, the FDA's chief vaccine regulator, said on a conference call Wednesday.

Aren't we rushing things?

There's an argument to be made that pushing these vaccines out as early as possible makes sense as kids head back to school and colder temperatures push people to spend more time indoors.

  • "We have a virus that is rapidly changing and we want to be able to have as much impact in terms of saving lives, preventing severe illness as we can," said Richard Besser, CEO of the Robert Wood Johnson Foundation and former acting director of the CDC.
  • Emerging data showing more younger patients with "long COVID" also factored in the decision to make the shots available to people age 12 and up.
  • Politics may also play a role, some suggest.
  • "The ideal time for individuals to get boosters would likely be late October to mid-November based on conversations we have had with experts. That is literally right before the election," Chris Meekins, an analyst for Raymond James, wrote in a note to clients.
  • One line of thought holds the Biden administration in pushing the shots now can prevent a significant uptick in cases before the midterms, Meekins said. That could avoid having a discussion about COVID and the need for boosters in the weeks before people go to the polls. "Both are viewed by Democratic political consultants as harmful to Democratic chances," Meekins wrote.

Do we really need an Omicron-specific booster?

The consensus is yes. But there still are questions whether it's worth the effort.

  • That's because the original mRNA vaccines continue do a good job of preventing severe illness, even though they're increasingly ill-suited to tackle Omicron.
  • Paul Offit, a vaccine researcher at the Children's Hospital of Philadelphia, told the journal Science that because the time between getting infected and becoming infectious to others is so short with COVID-19, the reformulated shots may not have a big impact.
  • He contrasted that with measles or rubella, which have a longer incubation period and give a vaccinated person's immune memory cells time to produce enough antibodies to prevent the disease from being passed on.

Should I get the same brand of booster as my original shot, or is mixing and matching better?

Pekosz said studies haven't shown significant differences between one combination over another. "Really whatever is available is just fine," Pekosz said.

How many people will get these new Covid vaccines?

Uptake will likely be lower in part due to fewer dollars available for outreach, Besser said. And then, there's pandemic fatigue.

  • "There are a lot of people who are just done thinking about COVID and taking any measures whatsoever to reduce their chances of getting it. That's concerning given that more than 400 people are still dying every day from COVID," Besser said.
  • "We believe less than one-third of the fully vaccinated will get this new booster between now and March 1, 2023," Meekins said. "At the high end, we believe 75M booster shots could be administered, though we expect that number to be much lower. We would not be surprised if it fails to crack 50M."

However, Meekins said: "If we start to see a significant wave, we expect vaccination demand to increase."

Editor's note: A quote from Andrew Pekosz, co-director of the Johns Hopkins Center of Excellence for Influenza Research and Surveillance, has been corrected to say: "If you know the vaccine platform works, just putting a new variant sequence into it shouldn't necessitate you do a full-blown clinical trial once you have all that data." It was previously misstated to say "should".

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