“The purpose of testing, in my opinion, is to identify asymptomatic people who are positive and get them the hell out of the contagion chain,” said Dr. John McDonough, a professor at the University of North Florida in Jacksonville who authored a book on epidemiology for nurses. “And if you don’t do that, all these places that are saying, ‘Oh gee, great, we don’t have any cases,’ wait in three weeks and see what happens.”