Millions of Americans traveled for Thanksgiving despite pleas not to do so from the Centers for Disease Control and Prevention. Dr. Deborah Birx of the White House Coronavirus Task Force says if you're one of them, assume you're infected, get tested and do not go near your friends or family members without a mask on. Because COVID-19 is a largely invisible threat, our brains struggle to comprehend it as dangerous. Dr. Gaurav Suri, a neuroscientist at San Francisco State University, explains how habits can help make the risks of the virus less abstract. Emergency room doctor Leana Wen discusses why it's tempting to make unsafe tradeoffs in day-to-day activities and how to better "budget" our risks.In participating regions, you'll also hear a local news segment that will help you make sense of what's going on in your community.Email us at considerthis@npr.org.