A Franklin County resident has become the third confirmed Missouri measles case tied to an Amtrak trip from Sedalia to Chicago, and health officials are asking anyone who visited several St. Louis-area businesses, including Busch Stadium, to watch for symptoms into early October, St. Louis Public Radio reported on Sept. 23.
The possible exposures happened from Sept. 12 through Sept. 14 at a ballgame, bars, restaurants and markets in St. Louis, Pacific and Chesterfield. Because measles symptoms can take up to 21 days to appear, the monitoring window for the last listed site runs through Oct. 5.
