The Onondaga County Health Department reports that 20 cases of Salmonella, scattered from late August through October 19, have been linked to Plainville’s Nature’s Fare Restaurant.  Several of those sick were hospitalized.  As of Thursday afternoon, the restaurant shut down, and will stay closed for a week.  Owner Mark Bitz says it will give them time to clean the place top to bottom, test their employees, and also give the restaurant a chance to review its practices.  "It’s hard to know — we may never know the exact source, but certainly all steps being taken by the facility are going to ensure this isn’t going to happen again," says Onondaga County health commissioner Dr. Cynthia Morrow.