For a list of what we should clean, how and when, we asked a bunch of germ experts. The biggest surprise? People with pets are six times more likely to get salmonella-based infections. Want to sanitize? Always clean before you sanitize. If chlorine comes in contact with dirt or soil, it can no longer sanitize. Thanks to our sources: Benjamin Chapman, the extension food-safety specialist for N.C. State; David Sweat, foodborne-disease epidemiologist with the North Carolina Division of Public Health; Douglas Powell, professor of food safety at Kansas State University; and Dean Cliver and Linda Harris with the University of California-Davis. --Kathleen Purvis/McClatchy Newspapers, (c) 2011, The Charlotte Observer (Charlotte, N.C.)