Scientists race to find new coronavirus mutations

There are warnings of a “pandemic within a pandemic” as coronavirus cases surge and more infectious strains of the virus are reported in at least 9 states. Scientists are racing 24/7 to identify thousands of new mutations that some fear may challenge the efficacy of vaccines. For Weekend TODAY, NBC’s Keir Simmons shares an exclusive look inside a genome sequencing lab that first identified the more infectious U.K. variant.