Variants are spreading across the U.S. Here's where they are, state by state.
More infectious Covid-19 variants have emerged around the world, and experts are saying the United States must adapt to a changed pandemic playing field.
According to the federal Centers for Disease Control and Prevention, these variants spread more easily, and it’s unknown whether the illness caused is more severe. The Pfizer-BioNTech vaccine was found to be only slightly less effective against the South African variant.
What hasn’t changed in the face of these variants: Experts maintain their recommendation that people wear masks.