Even if the country cut its rate of transmission in half — a tall order — some 650,000 people might become infected in the next two months. “We’re looking at something that’s catastrophic on a level that we have not seen for an infectious disease since 1918,” said Jeffrey Shaman, a professor of environmental health sciences at Columbia and the leader of the research team, referring to the Spanish flu... at least 1 in 5 Americans will be under orders to stay home in the coming days, and more states are expected to follow suit. But other places have resisted....