The war against COVID-19 has changed because of the highly contagious Delta variant, the U.S. Centers for Disease Control said, proposing a clearer message, mandatory vaccines for health workers and a return to universal masking. #News #Reuters #COVID19 #Deltavariant #coronavirus Subscribe: http://smarturl.it/reuterssubscribe Reuters brings you the latest business, finance and breaking news video from around the globe. Our reputation for accuracy and impartiality is unparalleled. Get the latest news on: http://reuters.com/ Follow Reuters on Facebook: https://www.facebook.com/Reuters Follow Reuters on Twitter: https://twitter.com/Reuters Follow Reuters on Instagram: https://www.instagram.com/reuters/?hl=en