The kitchen floor can be a breeding ground for bacteria and viruses. Wooden floors are particularly susceptible to contamination, which is why so many commercial kitchens are outfitted with tile floors. Unfortunately, even the grout between the tiles can harbor nasty bacteria. At home, wipe up spills right away with paper towels, and mop the floor daily. Sanitize wooden floors with a vinegar-and-water solution, and follow that up with a plain water rinse. If you have tile or vinyl floors, clean them with a solution of bleach and water, or ammonia and water, but never mix bleach and ammonia, which produces toxic fumes.