Former CDC Director Nancy Messonnier and former White House Covid-19 adviser Andy Slavitt join Sean at Code Conference in Los Angeles to explain the back and forth on vaccine booster shots.

Today’s show was produced and hosted by Sean Rameswaram, with help from Dylan Scott and Haleema Shah, edited by Matt Collette, engineered by Efim Shapiro and fact-checked by Laura Bullard.

Transcript at vox.com/todayexplained.

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