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What To Know About the New COVID Booster Shot

booster shot

New bivalent COVID-19 boosters approved by the FDA and CDC will help protect against the BA.4 and BA.5 variants. While the threat of new variants will always remain in the future, these boosters are expected to provide a better degree of protection compared to the original booster dose. That is especially important as COVID-19 continues to circulate.

“What’s very clear and consistent across these vaccines is they keep us from getting severe disease that could lead to hospitalization or death,” said Richard Martinello, MD, director of Infection Prevention for Yale New Haven Health.

Dr. Martinello explained what sets these boosters apart and why eligible recipients should get vaccinated.

What does bivalent COVID-19 booster mean?

Bivalent means there are two different vaccinating components in the vaccine. These boosters from Pfizer and Moderna contain two different mRNA components. One is the same RNA as the original vaccine and booster, while the second is a new mRNA which was developed to target the BA.4 and BA.5 variants, which currently are causing nearly all COVID occurring in the U.S. When people get this new booster dose, they will be getting protection against both the original strain and these new variants.

This is a common approach to vaccines. For example, our current flu vaccines are quadrivalent which means they protect us against four different strains of flu at the same time.

Is it true this booster did not have to undergo the same rigorous trials that the original vaccine had to go through?

The FDA handled the approval of this vaccine in a manner similar to how they approached the flu vaccine over the past several decades. Because we already understand how this vaccine works, and mRNA vaccines in particular, the FDA and CDC agreed that it was safe to approve the vaccine without the trials needed for the original vaccine authorization.

“At this point in time our COVID vaccinations are probably the most extensively studied vaccines that are in use,” said Dr. Martinello. “In the United States alone, we have used over 600 million doses. There have been billions of doses used worldwide, and with that extensive experience, that allows a more abbreviated regulatory process.”

Why should I get the new booster if I already got boosted months ago?

If it has been at least two months since your last shot, you should get the new booster due to the high rates of COVID-19 that continue to circulate. It may seem like we have had to get a lot of COVID-19 shots but remember that many vaccines require multiple doses. Even the flu shot requires two doses for younger children. In the future, we may need to get a COVID-19 booster along with our yearly flu shot every fall.

In addition, getting boosted helps to reduce transmission of COVID-19. So, when we get boosted, we help protect others along with ourselves. Should I wait to get the new booster along with my flu shot? We typically receive flu shots in October, so it’s better to get the COVID-19 booster once it becomes available to you. This is especially important for anyone who may be at risk for more severe cases of COVID-19, such as those who are immunocompromised and those who are pregnant.

However, if you decide to wait to get the booster, it is perfectly fine to get it on the same day as your flu shot.

Learn more about booster eligibility.