60 Minutes 5/31

Until a vaccine is found, plasma therapy has been helping COVID-19 victims get better. Bill Whitaker has the story. Raw sewage from Tijuana is appearing on southern California's coasts. Lesley Stahl reports. And NASA is attempting to find signs of ancient life on Mars with the launch of Perseverance. Anderson Cooper has the story on this week's "60 Minutes." See Privacy Policy at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.