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What you need to know

  • The updated boosters are bivalent vaccines that aim to offer better protection against BA.5.
  • The new shots are just as safe as the original vaccines.
  • The updated boosters will be critical to preparing for a potential fall or winter surge.

Earlier this month, the FDA and CDC expanded the use of updated COVID-19 boosters to children ages 5 and older. The modified doses are now available at pharmacies, community health centers, and doctors’ offices for everyone 5 and older who is at least two months out from completing their primary series or receiving their last booster. Here is what you need to know about how these boosters are different and why we need them for the fall and winter.

How are the updated boosters different from our original vaccines?

The updated boosters developed by Pfizer and Moderna are bivalent vaccines, or vaccines that protect against more than one strain of a virus. In this case, the modified doses target the original COVID-19 strain and the BA.4 and BA.5 Omicron subvariants. The goal of the bivalent boosters is to offer better protection against BA.5, which currently makes up more than 60 percent of circulating COVID-19 viruses in the country. The boosters will also ideally provide broader protection against other Omicron spinoffs, which have been on the rise globally.

Who is eligible to receive an updated booster?

Pfizer’s Omicron booster is authorized for people 5 and older, while Moderna’s is authorized for people 6 and older. The FDA says people can safely receive an updated booster at least two months after their last shot. With holiday season coming up and new immune-evasive variants spreading, everyone who is eligible should get their bivalent booster as soon as possible. It takes a couple of weeks for effectiveness to kick in, so if you want to be protected by Thanksgiving, get your booster by the first week of November.

Where can you get a fall booster?

The doses are being offered at pharmacies, community health centers, and doctors’ offices around the country. You can now schedule an appointment at CVS or Walgreens, or use Vaccines.gov to find sites near you offering the new shots.

Why do we need updated boosters?

The original COVID-19 vaccines continue to be effective against severe disease, but they do not offer strong protection against Omicron infection. As we saw during the Omicron wave last winter, a surge in infections inevitably leads to a rise in hospitalizations and deaths.

The updated boosters will ideally provide more targeted protection against BA.5 infection and severe disease. By decreasing the risk of infection, the new shots would in turn minimize the number of hospitalizations and deaths, especially among individuals who are immunocompromised. Scientists also hope that the updated boosters will provide longer-term immunity and broader protection against future variants.

Are the updated boosters safe and effective?

Federal health officials stress that the modified shots are just as safe as the original vaccines. The FDA did not require the updated boosters to go through the full authorization process, which includes human clinical trials, because the shots use the same foundation as the already authorized original vaccines. This sped-up process is similar to the one used for the flu vaccine, which is altered each year to target the strains most likely to be dominant.

The effectiveness of the updated boosters, however, is less clear. Since the modified shots did not go through human trials, there is no direct data on how well they work. Pfizer and Moderna did present promising data on effectiveness from animal trials. Data from previously tested bivalent vaccines—which targeted the beta and BA.1 variants—also suggest that these types of shots have the potential to increase effectiveness against infection and trigger a more durable immune response.