Pfizer, Moderna ask FDA to authorize additional COVID-19 booster shots

A fourth dose of the COVID-19 vaccines could be on way.

Thursday, Moderna asked the FDA to authorize a second COVID-19 booster of its vaccine for all adults.

Two days earlier, Pfizer-BioNTech requested approval of a fourth shot for seniors 65 and older.

Microbiologist Dr. Amber Schmidtke of the University of St. Mary says the additional boosters may be needed because the vaccines' immunity begins to wane about 4 to 6 months after getting a shot.

"So, as a person with an underlying condition, I am interested in getting an additional booster," Schmidtke says.  "Whatever it takes, really, to prevent getting sick, to prevent long COVID."

The Food and Drug Administration and the CDC will ultimately decide whether to authorize and recommend a fourth shot of the mRNA vaccine.

But, Schmidtke, who publishes an online newsletter tracking the pandemic in Georgia, supports the idea of an additional booster shot for all adults, not just those in high risk groups.

"What we've seen in the pandemic, from the start is that you can be a completely healthy, a young adult, and still end up with severe COVID or potentially long COVID," she says. "So, I think it is important to make this available to all adults, regardless of underlying health conditions. Because, ultimately, those who want to be protected want to have the most effective immune system they possibly can, and they can get that with the vaccine."

Schmidtke says she knows many Americans are tired of the pandemic, and hesitant to get yet another COVID-19 shot.

But, she says this virus is a moving target.

"It's unrealistic to think there is going to be a silver bullet, where you have an evolving virus," Schmidtke says.  "Yes, the doses you've received previously worked very well for the variant at the time the vaccine was created.  But, the reality is we change the flu vaccine every year because we need to adapt to an evolving virus and I think the same may be true for COVID-19."

She believes the COVID-19 vaccine could become a yearly vaccine, much like the flu vaccine.

"Again, because we have not done the work of eliminating this virus, we are going to continue to have COVID in our lives. So, it will be important to have availability of vaccines and boosters.  So, I think it will continue to look like the annual flu vaccine."

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