By Stephanie Stahl

PHILADELPHIA (CBS) — COVID-19 cases are surging in the Philadelphia area as the White House prepares to recommend a booster shot for many vaccinated Americans. It’s that summer surge that prompted the expected recommendation, but boosters still have to be approved by the FDA.

Booster shots are currently only available to people who are immunocompromised.

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Americans who received the Pfizer or Moderna vaccine could start getting a booster shot as early as mid-September if the FDA approves the plan being recommended by the Biden administration.

“In getting a booster, what we will likely see is higher vaccine effectiveness from infection, we will have less breakthrough cases,” Scott Hensley, a professor of microbiology at the University of Pennsylvania, said.

Hensley says the current vaccine dosing is working extremely well at preventing severe disease, but research is showing protection from infection doesn’t last at a high level.

“Antibodies that are elicited by vaccines, they decrease over time, and not only that, the virus has changed quite a bit,” he said.

The more contagious Delta variant that’s causing the fourth COVID-19 surge has elevated the need for a booster. The timing would be eight months after the second dose.

The third shot would likely be the same brand as the first two.

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“This is a dynamic process and the data will be evaluated,” Dr. Anthony Fauci said. “One thing we are doing is we are preparing.”

A spokesperson for the Philadelphia Health Department says the city has the capacity to handle an additional 20,000 doses per week in September if needed for boosters, but they can’t do any planning until how the city sees how and if the FDA approves the plan.

Hensley said he’s concerned about vaccine supplies and how the booster plan would be rolled out.

“Of course I’m concerned,” he said. “If you look at how the original vaccine was rolled out, that wasn’t super smooth.”

He also thinks instead of boosters, the U.S. should send vaccines to countries that need them.

“This pandemic’s not going anywhere until we get vaccines disturbed across the world,” Hensley said.

The booster plan does not currently include people who received the Johnson and Johnson vaccine.

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Health officials say they’re waiting for more data on the J&J shot before making a determination.

Stephanie Stahl