(Otis, OR)  --   Serena Proffitt died at a Portland hospital Monday of complications from the infection, which is believed to have been contracted after she and her five-year-old friend shared a turkey sandwich at a restaurant in Otis.  The boy also became sickened, and is being treated at a hospital in Tacoma, Washington.  Lincoln County health officials are scheduled to have a news conference later this morning to give an update on the E. coli investigation.