New, mutated strains of the coronavirus are causing worry around the world as health officials race to vaccinate as many people as possible. Dr. Jon LaPook reports on why the new strains are popping up. “60 Minutes” is the most successful television broadcast in history. Offering hard-hitting investigative reports, interviews, feature segments and profiles of people in the news, the broadcast began in 1968 and is still a hit, over 50 seasons later, regularly making Nielsen’s Top 10.