Across America, people are afraid of a vegetable. Or is it a fruit? The ongoing salmonella outbreak has now sickened over 1000 people and forced many farmers to leave their tomatoes rotting on the vine. But the source of the outbreak remains unknown. Experts are now questioning whether it came from tomatoes at all. Madeleine Brand talks to NPR's Allison Aubrey to find out more about the outbreak and the FDA's hunt for its source.