The number of people sickened in an E. coli outbreak associated with McDonald’s has grown.
The Centers for Disease Control and Prevention (CDC) said Friday that 75 people have been identified as having been infected with the specific strain of E. coli 0157:H7 in 13 states over a two-week period between Sept. 27 to Oct. 10. That’s 26 more than had been previously reported earlier this week.
Of the 61 people for whom information is available, 22 have been hospitalized, and two people developed hemolytic uremic syndrome (HUS), a serious condition that can cause kidney failure. One person—an older adult in Colorado—died, but that patient did not develop HUS, the CDC said.
The CDC also warned that the true number of people sickened in this outbreak is likely much higher than what has been reported so far, and may not be limited to the states identified. Some of those infected also had traveled from other states.
State and local officials have interviewed 42 of those who were infected. All of them said they had eaten at a McDonald’s, and 31 of them remembered eating a Quarter Pounder specifically.
Investigators are still focusing on the slivered onions from the supplier Taylor Farms, which were served on Quarter Pounders. The Food and Drug Administration, which regulates produce, sees the slivered onions as a likely source of the outbreak—noting that the diced onions used at McDonald’s are not implicated.
Taylor Farms this week recalled some of its yellow onion products, and McDonald’s and several other restaurant chains have pulled onions from some restaurants.
McDonald’s in an update on Friday pointed the blame at onions supplied by a Taylor Farms facility in Colorado Springs. The company said that onions from that facility were distributed to 900 locations in Colorado, Kansas, Wyoming and portions of other states in the area.
Some of those locations are transportation hubs, which might account for illnesses in additional states, the company said.
But Taylor Farms supplies more restaurant companies and retailers in the area than just McDonald's, though no other company besides McDonald's has yet been implicated in the outbreak. Nevertheless, McDonald's highlighted other chains' decision to pull onions from their menus and called on other companies to be “transparent” on the issue.
“We fully expect others in our industry will also follow the imperative to be transparent in service of public health, and we expect health authorities will continue to provide updates.”
The beef patties used for Quarter Pounders also remain a potential source of the contamination.
McDonald’s has temporarily taken Quarter Pounders off the menu in 12 states while the investigation continues, the CDC said.
The U.S. Department of Agriculture’s Food Safety and Inspection Service, or FSIS, is conducting a traceback on the hamburger patties to determine if that was the source.
Other items, including cheeseburgers, hamburgers, Big Macs, McDoubles and Double Cheeseburgers, are not affected, the company said.
UPDATE: This story has been updated to include information from McDonald's.
Jonathan Maze contributed to this report.
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