Nestlé Recall Leaves A Mystery in Its Wake

Nestlé, which has a 41 percent share of the prepared cookie dough market, has not estimated the cost of the recall, MacDonald said.

Investigators have not confirmed the presence of E. coli 0157 in any Nestlé product; they are testing samples of dough collected from the plant as well as from victims. But William E. Keene, chief epidemiologist for the state of Oregon, said he was "100 percent" certain that the culprit was the cookie dough. "Virtually everyone [who got sick] ate the same brand of cookie dough," he said. "I have absolute confidence in the conclusion."

Because the appearance of E. coli 0157 in cookie dough is so unusual, investigators are looking at a broad range of possible factors, analyzing the ingredients, the plant's equipment and interior, the health of workers and whether the facility is located near cattle. Federal officials are also considering whether the dough might have been intentionally contaminated.

State health officials first noticed cases of E. coli 0157 emerging in March. Initially, they suspected ground beef or strawberries. But after interviewing victims, state officials and the CDC compared notes during a conference call Tuesday and settled on the refrigerated cookie dough as the prime suspect.

The risk usually associated with cookie dough is salmonella, a bacteria that can be found in raw eggs contained in the dough. Nestlé's cookie dough is packaged with labels warning consumers not to eat it raw. But people tend to disregard the warning -- 39 percent of consumers eat raw cookie dough, according to Consumer Reports. It has become such a popular snack that many ice cream makers have developed a cookie dough flavor.

William Marler, a prominent food safety lawyer in Seattle who is representing six of the E. coli 0157 victims, said Nestlé's warning label is not a defense. "It doesn't absolve them of liability," he said.

E. coli refers to many kinds of bacteria, most of which are harmless or even beneficial. But certain types, including E. coli 0157, produce a toxin that can cause severe illness and even death in humans. The E. coli 0157 bacterium lives in the intestines of cows and other animals -- goats, sheep, deer and elk -- and is found most often in ground beef. But over the past decade, a number of E. coli 0157 illness outbreaks have been associated with green, leafy produce, such as spinach.

"Food-borne diseases are generally a moving target," Hedberg said. "We can't get too comfortable thinking we know how these organisms behave."