How should raw tomatoes be handled prior to serving or eating them?

• Before handling fresh tomatoes, wash your hands with hot, soapy water for 20 seconds, and dry them with a paper towel.
• Wash and sanitize the counter top, cutting board, and utensils. For this purpose, it’s handy to have a spray bottle with a solution of 1 teaspoon of chlorine bleach per quart of water, but you can also use a store-bought sanitizing solution. (If your utensils and cutting board have been washed in the dishwasher, that will suffice.)  After using a bleach or other sanitizing solution, wipe all surfaces and utensils with a cloth dampened with clear water.
• Wash all tomatoes thoroughly in a clean sink under  clean, running water, even if you don't intend to eat the skins. Gently rub each tomato with your hands to help remove dirt and bacteria.
• It’s important to prevent cross-contamination. Therefore, don’t use the same cutting board for raw meat or poultry that you use  for fruits  and vegetables to be consumed raw--unless it can tolerate hot-water washing and soaking in a sanitizing solution. 
• When slicing or chopping tomatoes, be sure to cut off and discard the stem. Pathogens that can cause food-borne illness may reside in this area.
• After slicing or dicing tomatoes, wash hands, utensils, cutting board, and counter well with hot soapy water, bleach mixture, or sanitizing solution.  Then wipe with a damp cloth to remove sanitizing residue.

 
Source(s):
Texas A&M University "Safe Handling of Fresh Tomatoes"
Susan Brewer, Ph.D.  University of Illinois, Department of Food Safety and Human Nutrition