CNN chief medical correspondent Sanjay Gupta, MD, offers an accessible, data-packed answer to our biggest questions about Covid-19: What have we learned about this pandemic and how can we prepare for—or prevent—the next one?As America’s favorite frontline Covid-19 health journalist, Dr. Sanjay Gupta has barely left his primetime seat in his makeshift studio basement since the pandemic began (other than to perform brain surgery). He’s had insider access to the drama’s unfoldin