As public health officials struggle to get even a single dose of the COVID-19 vaccine into all eligible Americans, Pfizer and BioNTech have announced the companies are going to ask the Food and Drug Administration for authorization to provide a booster dose of its vaccine.

Pfizer says getting a third shot within a year of the first two would increase immunity and protect against some of the most worrisome variants.

But in an unusual move, the Centers for Disease Control and Prevention and FDA immediately released a statement saying “not so fast!” They’re telling Americans that a final decision will certainly include drug company data, but will only happen “when science demonstrates they are needed.”

Here & Now‘s Peter O’Dowd talks to Dr. Peter Hotez, co-director of the Center For Vaccine Development at Texas Children’s Hospital.

This article was originally published on WBUR.org.

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