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Pfizer says its COVID-19 vaccine is shown to be extremely effective in young teenagers.
Esteban Felix/APScientists are growing concerned the U.S. may be headed for a fourth wave. COVID-19 cases are rising rapidly, mirroring an increase in many countries around the world.
Harvard epidemiologist Bill Hanage tells NPR he's worried another surge in the U.S. will fuel the spread of the variant known as B.1.1.7 .
In the meantime, there's new evidence that vaccines from Pfizer and Moderna are effective at preventing viral spread — and that they produce "robust" antibody response in children ages 12-15. NPR's Joe Palca has more.
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This episode was produced by Brent Baughman, Brianna Scott and Lee Hale. It was edited by Sami Yenigun with help from Rob Stein and Wynne Davis. Our executive producer is Cara Tallo.