Investigators Suspect Multiple E. Coli Strains in Tainted Cookie Dough

By Lyndsey Layton
Washington Post Staff Writer
Friday, July 10, 2009

Federal and state investigators found two different strains of E. coli bacteria in samples of recalled Nestlé Toll House cookie dough, and neither matches the type that has caused a national outbreak of illness, suggesting that the product may have been contaminated by multiple kinds of bacteria.

The Food and Drug Administration said yesterday that laboratory analysis of E. coli O157 found in a sample of cookie dough at Nestlé's Danville, Va., plant did not match the strain that is believed to have sickened 72 people in Maryland, Virginia and 28 other states.

The state of Minnesota reported that preliminary tests of a package of Nestlé cookie dough taken from a household where two people were sickened by E. coli O157 showed the product was contaminated with a third deadly strain of bacterium, E. coli O124.

Meanwhile, federal officials said yesterday that they were finishing their probe of Nestlé's Danville plant, which involved more than 1,000 microbiological tests. They remained stumped. "I think it probably is going to remain a mystery," said David Acheson, assistant commissioner for food safety at the FDA.

Of those sickened, 34 have been hospitalized. None has died.

Investigators did not find E. coli inside the Danville plant, on equipment, in raw ingredients or in additional samples of cookie dough, Acheson said.

E. coli O157 lives in the intestines of cows, sheep and other animals and is most often associated with ground beef. None of the ingredients in cookie dough -- eggs, milk, flour, chocolate, butter -- is known to host the bacterium.

Nestlé voluntarily recalled 30,000 cases of its refrigerated cookie dough on June 19 after officials at the FDA and the federal Centers for Disease Control and Prevention suspected that dozens of cases of E. coli-related illness were linked to the product.

Nestlé, which temporarily shut down its plant and dismantled its equipment, tentatively began producing cookie dough on Tuesday, after finding new suppliers for flour, eggs and margarine, a spokeswoman said.

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