A hand reaches for a vaccine vial from above.
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What you need to know

  • Pfizer and Moderna say boosters that target BA.5 could become available in September.
  • Everyone who is eligible for a first or second booster should get one right away.
  • Getting a booster now will give you enough time to receive a reformulated shot before a possible winter surge.

The spread of BA.5 has brought average U.S. case counts to a high plateau of roughly 130,000 per day—a number that is likely an undercount due to the popularity of at-home testing. Meanwhile, hospitalizations are also increasing, though the numbers remain well below previous peaks.

Despite the magnitude of the current COVID-19 wave, the FDA decided against expanding eligibility for second boosters to younger Americans. Instead, the agency says that people under 50, unless they are immunocompromised, should wait for the reformulated shots to get their second booster.

When will the updated boosters become available?

The Biden administration expects updated COVID-19 boosters to become available in September. Pfizer and Moderna had originally said they would not be able to deliver reformulated shots until October at the earliest, but both companies recently assured federal officials that they could speed up their timelines and be ready in early September.

The federal government has already purchased 105 million updated Pfizer booster doses and secured 66 million updated Moderna booster doses, though these agreements are dependent on FDA authorization and CDC recommendation.

Why do we need updated boosters?

The COVID-19 virus has been mutating to become better at evading our immune defenses, both from vaccination and from prior infection. Although our current vaccines and boosters continue to reduce the risk of severe illness, their effectiveness against infection has dropped significantly.

In response, independent vaccine experts and federal regulators decided that there is a need for revised vaccine formulations that target more recent COVID-19 strains ahead of a possible winter surge. In June, the FDA advised vaccine manufacturers to create a bivalent booster by adding a component to the current vaccines that targets the Omicron subvariants BA.4 and BA.5.

Should I wait for the reformulated shots to get boosted?

Everyone who is eligible for a booster should get one right away and should not wait for the revamped vaccines. This means everyone ages 5 and older should get their first booster. Everyone 50 and older, and individuals with certain immune deficiencies, should get their second booster. The FDA said that people under 50 who are not immunocompromised should wait for the reformulated shots to get their second booster.

Since there needs to be a certain amount of time between each immune boost for it to be safe and effective, it’s important to get your shots as soon as you become eligible. Getting a booster now will give you enough time to receive a reformulated shot before a potential winter surge. If you were recently infected with a breakthrough case, wait until your symptoms have resolved and you’ve ended isolation to get your next shot. Vaccinated people who received monoclonal antibodies as part of their COVID-19 treatment will need to wait 90 days before getting a booster. 

How safe and effective will the updated boosters be?

As of now, it’s unclear how effective these updated boosters will be as they are still in the testing phase. In June, both Pfizer and Moderna announced that their BA.1-specific boosters produced a stronger immune response than their current shots. But the companies have since shifted gears to develop shots that target BA.5. 

In terms of safety, the modified shots would need to pass the regulatory requirements of FDA authorization and CDC recommendation before being administered to the public.