 Just ahead of the 4th of July holiday, cases of COVID are on the rise. CBS's Stacey Lynn reports. Infectious disease specialist Dr. William Schaffner says the newest variants are grandchildren of Omicron. The most common variant. And he says they're... Very, very contagious. But because most of us have had some form of COVID or a vaccination before... What we call our population immunity is much better. So there are fewer severe diseases.