Eat Spinach...Get Diarrhea

The number of people sickened by an E. coli outbreak traced to tainted spinach rose to 109 on Sunday, as federal officials announced more brands recalling their products.

"This is unquestionably a significant outbreak in terms of E. coli," said Dr. David Acheson, chief medical officer with the Food and Drug Administration's Center for Food Safety and Applied Nutrition.

Natural Selection Foods LLC, the world's largest producer of organic produce, has been linked to the infected greens, prompting a recall of 34 brands. Those brands include the company's own labels and those of other companies that had contracts with Natural Selection, based in San Juan Bautista, California, to produce or package its spinach.

On Sunday, River Ranch Fresh Foods of Salinas, California, added to its recall spring mixes containing spinach that were sold under the labels Hy Vee, Fresh and Easy, and Farmers Market, FDA officials said. All contain spinach purchased from Natural Selection, they said.

The recalls came as the Centers for Disease Control and Prevention intervened to help investigate the outbreak, which has killed a 77-year-old Wisconsin woman, officials said.