The study they conducted, prompted by recent romaine outbreaks, included 284 samples of varying greens including kale, spinach, lettuce and others. In that selection, six samples were tainted with Listeria monocytogenes.
Martin Wiedmann, a food safety professor at Cornell University, told USA TODAY that Listeria monocytogenes causes disease. According to the Centers for Disease Control and Prevention, 1,600 people are infected by the bacteria species yearly, and about 260 die.
“It’s always concerning to find a bacteria that can make people sick in foods that won’t be cooked,” Brittany Behm, spokesperson at CDC told USA TODAY.