There's a fascinating article on Yahoo News. 
A study has found that the typical office desk harbors more bacteria than a workplace restroom, and women's workspaces have more germs -- three to four times as much -- than their male counterparts.
Why were the women's desks germier? University of Arizona professor Charles Gerba, a professor of soil, water and environmental sciences, found that 75% of women had munchies in their desks, which can harbor microorganisms.
Do I have food in my desk? You bet I do.
I think we all need an increased awareness of bacteria, etc., without becoming nuthouse cases. A few years back I started washing my hands vigorously on many occasions during the day, and have had much less illness.
A test on a cruise ship once where the captain had a fluorescent substance on his hands and shook hands with all of us going to dinner was impressive. They turned of the lights and the whole room was lit up: not only hands, but salt shakers, plates, chairs, etc. And, yes, we have to be careful with food. Lisa: try walking to a central spot for your food -- and you will get some exercise, too!
That solves it. I'm moving my desk into the bathroom.
I too have some food stashed... I only hope that nothing bigger than a bacteria tracks it down and tries to wrestle it from me.