Delta variant of COVID-19 is ‘by far the most contagious we have seen,’ doctor says

Dr. Ashish Jha, dean of the Brown University School of Public Health, tells TODAY that the Delta variant of COVID-19 is “by far the most contagious variant of the virus we have seen throughout the whole pandemic” but says people who have been vaccinated needn’t worry. But he worries about “large pockets” of Americans who are still unvaccinated, and has doubts about whether President Biden’s goal will be reached: “I’m not sure we’re going to hit that number.”