Will we need booster shots?

The CDC says it is preparing for the possibility that booster shots will be needed later this year.

"What we really don't know is how long that protection will last," said CDC Director Dr. Jennifer Walensky during a discussion on Instagram with actor Jennifer Garner.

She indicated the CDC was getting ready to distribute booster shots late this year, if necessary, through health providers, akin to how you get a flu shot.

"It is critical we don't get into this situation again," Dr. Walensky explained. "So we are doing those studies now to prepare for the worst-case scenario and hope that it doesn't come."

USF virologist Dr. Michael Teng says Pfizer and Moderna's ongoing studies on the effectiveness of their own vaccines are tracking whether there are any dropoffs in antibodies. Pfizer and Moderna have said their vaccines are still 90 percent effective after six months.

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"There is no cheating time," said Dr. Teng. "What we know is eight months out, there is still quite a bit of immunity from both mRNA vaccines."

The other question the CDC has is how the vaccines will do overtime against the variants.  

So far, they have shown to be excellent against the most common ones, but booster shots are already being designed to react to the newest ones.

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"They just released some data it seems to work pretty well," said Teng. "These platforms are easily changed to be directed to whatever variants may arise."

Dr. Teng says there is confidence that the vaccines will work for at least a year.

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