As more US state leaders announce hopeful timelines for a return to normalcy, one expert says there's something that could delay how quickly we get there.
Mandatory Credit: Paul Frangipane/Bloomberg/Getty Images
Stories this photo appears in:
Not reaching herd immunity by the fall could have dire consequences, medical expert says
About 2.4 million people in the United States are now receiving Covid-19 vaccinations daily, but one medical expert thinks the nation may not reach herd immunity this year if more people can't be persuaded to get a shot.
