The US remains among nations with the highest rate of new Covid-19 cases, driven mostly by a surge in the South, where many states are lagging in getting people vaccinated against the coronavirus. "This is starting to look really ominous in the South. ... If you look at rates of transmission in Florida and Louisiana, they're actually probably the highest in the world," Dr. Peter Hotez, the dean of the National School of Tropical Medicine at Baylor College of Medicine, told CNN's Anderson Cooper on Friday. On a state-by-state comparison, Louisiana has the highest rate of new cases per capita,...