CDC Director Robert Redfield has signed off on the vaccine, allowing immunizations to begin Monday. The shots should go to front-line health-care workers and residents at long-term care facilities first, where the virus has had a devastating toll, according to CDC guidelines. It's a race against time to ramp up the vaccine program into a mass inoculation campaign as thousands of people die everyday from Covid-19, with the toll only expected to increase over the holidays. More than 2,300 deaths were recorded Saturday, following over 3,300 deaths Friday. New infections continue to explode, with more than 219,000 cases reported yesterday. Jeff Kowalsky | AFP | Getty Images