Claudia Pfeil, MD, examines Charles Lin, of Alhambra, who has the flu symptoms at Pasadena Urgent Care Health Care Partners in Pasadena Friday, January 5 2018. A mighty wave of flu has gripped the nation and Southern California. LA County is seeing widespread influenza which means emergency rooms and urgent cares are packed. (Photo by Walt Mancini/Pasadena Star-News/SCNG)