(Craig Hudson for The Washington Post)A record-breaking surge in U.S. coronavirus cases is being driven to a significant degree by casual occasions that may feel deceptively safe, officials and scientists warn — dinner parties, game nights, sleepovers and carpools. But public health officials nationwide say case investigations are increasingly leading them to small, private social gatherings. From March through September, the average number of contacts identified in Maine coronavirus investigations was 3.5. Calderon started to feel ill a few days later, and she tested positive for the coronavirus on Oct. 20. (Andrew Kelly/Reuters)McDonald said he hopes that might help with an alarming widening of social groups and casual encounters, particularly among youths.
