Tonight on the Last Word: U.S. cases of coronavirus rise above 1,600 as the death toll climbs to 41. Also, the U.S. stock market suffers its worst day since 1987 as fears intensify over the coronavirus pandemic. Plus, Trump causes confusion over travel restrictions. And Rep. Katie Porter returns to discuss getting Trump’s CDC director to commit to making testing free . Ron Klain, Dr. Ashish Jha, Dr. Sheri Fink, Jason Furman and Sara Nelson also join Lawrence O’Donnell.