COLORADO, USA — Beef patties that were collected from Colorado McDonald's locations that are associated with an ongoing E. coli investigation have tested negative for the bacteria, the Colorado Department of Agriculture said.
The E. coli outbreak linked to McDonald's Quarter Pounders has sickened at least 75 people across 13 states and is blamed for the death of one person in Mesa County in western Colorado. The focus of the initial investigation was on the slivered onions and beef patties used by the chain for Quarter Pounders.
On Tuesday, the Colorado Department of Agriculture received multiple lots of fresh and frozen beef patties collected from Colorado locations associated with the outbreak. They tested those samples and found they were negative for E. coli. The department said they've completed all of the beef testing, and don't anticipate getting any more samples.
No definitive source of the outbreak has been identified, officials with the U.S. Food and Drug Administration said, but early information analyzed by the FDA showed that uncooked slivered onions used on the burgers “are a likely source of contamination,” the agency said.
McDonald’s has confirmed that Taylor Farms, a California-based produce company, was the supplier of the fresh onions used in the restaurants involved in the outbreak, and that they had come from a facility in Colorado Springs. McDonald's said they removed slivered onions from that facility from their supply chain on Tuesday.
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“We have made the decision to stop sourcing onions from Taylor Farms’ Colorado Springs facility indefinitely,” McDonald's said in a statement released late Friday.
Taylor Farms said Friday it had preemptively recalled yellow onions sent to its customers from its Colorado facility and continues to work with the CDC and the FDA as they investigate.
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Since the beef patties were ruled out as the source of the outbreak, McDonald's said they will resume selling Quarter Pounders in all restaurants within the next week. Quarter Pounder sales will resume "on a rolling basis based on delivery and resupply operations," the company said.
The 900 restaurants that previously received slivered onions from Taylor Farms’ Colorado Springs facility will be selling the burgers without slivered onions, the company said. Those restaurants are in Colorado, Kansas, and Wyoming, as well as portions of Idaho, Iowa, Missouri, Montana, Nebraska, Nevada, New Mexico, Oklahoma and Utah.
The Associated Press contributed to this report.