A judge’s ruling striking down the federal mask mandate on domestic flights in the U.S. has been met with celebration, concern and confusion.

The Biden administration plans to appeal the ruling if the Centers for Disease Control and Prevention decide there’s a public health need. Until then, it’s up to individual passengers to decide whether to mask up on most flights.

We discuss the science behind that decision with Dr. William Schaffner, a professor of infectious diseases at Vanderbilt University School of Medicine.

This article was originally published on WBUR.org.

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