McDonald’s Says Tests Rule Out Beef Patties as Source of E. Coli Outbreak

The company said it would put Quarter Pounders back on the menu, without the raw onions that were considered the likely source of the bacteria.

McDonald’s announced on Sunday that tests in Colorado had ruled out its Quarter Pounder beef patties as the source of a deadly E. coli outbreak, and said that the popular burger would be back on the menu at thousands of locations in a dozen states.

But the company said that in 900 of those sites, Quarter Pounders would not be topped with raw slivered onions — which federal regulators have identified as the likely culprit in the outbreak that health officials said had sickened 75 people and caused the death of one Colorado resident.

In a statement, McDonald’s cited tests conducted in Colorado, the state that had the most cases reported in the outbreak. On its website, the state’s Agriculture Department said that tests were done on “dozens of subsamples from all the lots and all samples were found to be negative for E. coli.”

Colorado health officials tested beef samples from the two beef suppliers that provided patties to the 900 affected locations in a dozen states, McDonald’s spokesmen said.

The company said it was not aware of any other state health agency that was still testing the beef patties for E. coli.

As for the slivered onions, McDonald’s said on Friday it would stop buying onions from the Colorado Springs site of its major regional supplier Taylor Farms, a multistate producer of vegetables and fruits. Last week, Taylor Farms recalled several yellow onion products — among them diced and slivered — because of “potential E. coli contamination.”