CNN — The E. coli outbreak linked to McDonald’s Quarter Pounders has led to 75 illness across 13 states, including 22 hospitalizations and one death, according to new data posted Friday by the US Centers for Disease Control and Prevention and the US Food and Drug Administration.
Two of the hospitalized patients had hemolytic uremic syndrome, a serious complication that can develop from an E. coli infection. The older adult who died had underlying conditions but did not develop this syndrome.
The CDC opened the investigation on Tuesday, initially reporting 49 cases in 10 states – including 10 hospitalizations and one death. It can take weeks to determine whether an illness is part of an outbreak and these numbers were expected to grow.
Most of the illnesses related to the outbreak continue to be in Colorado, according to the CDC. Michigan, New Mexico and Washington have also been added to the list of states with reported illnesses, along with Iowa, Kansas, Missouri, Montana, Nebraska, Oregon, Utah, Wisconsin and Wyoming. But the agency notes that the outbreak may go beyond those states.
Federal authorities say that they are still working to confirm the specific source of the bacteria, but the US Food and Drug Administration says that the slivered onions or beef patties on Quarter Pounder sandwiches are the likely source of contamination.
Among those who have been interviewed, all reported eating at McDonald’s and the vast majority had eaten a beef hamburger, according to the FDA.
“The FDA is using all available tools to confirm if onions are the source of this outbreak,” an agency spokesperson said in a statement. “This includes working with federal and state partners and the companies involved to collect and evaluate records and distribution information as part of our traceback investigation. FDA and state partners are also collecting onion samples for analysis.”
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