U.S. health officials are doubling down on advice to wear masks and stay physically distant from others as concern grows over new COVID variants.
CDC Director Rochelle Walensky said she expected the virus to mutate.
The U.K. variant has now been detected in 29 states. And the first U.S. cases of the South African variant have been reported in South Carolina.
Multiple vaccines, approved and in development, appear to protect against all forms of COVID but seem less effective against the South African variant.
Dr. Anthony Fauci said, "This is a wake up call to all of us that we will be dealing as the virus uses its devices to evade pressure, particularly immunological pressure that we will continue to see the evolution of mutants.