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McDonald’s Quarter Pounders have been linked to a multistate E. coli outbreak that has killed at least one person, according to the U.S. Centers for Disease Control and Prevention.
So far, around 50 people have been reported infected, with 27 infections occurring in Nebraska and nine in Colorado, according to the CDC.
Officials estimate that the actual number of people infected is probably much higher as it usually takes three to four weeks to determine if a sick person is part of an outbreak, and also because many people recover without being tested for E. coli.
Ten people have been hospitalized — including a young child diagnosed with hemolytic uremic syndrome, a dangerous condition that damages blood vessels in the kidneys. One older person has died in Colorado.
Most of the people infected reported eating a McDonald’s Quarter Pounder hamburger prior to becoming ill.
The CDC is working to identify the specific ingredient responsible for the outbreak and is focusing on two in particular: fresh slivered onions and fresh beef patties.
In response, the fast food chain has proactively removed the onions and patties used for the burgers from stores in the affected states, according to the CDC. As a result, Quarter Pounder hamburgers will be temporarily unavailable in some states.
The outbreak began around Sept. 27 and no infections have been reported in California as of yet. But in addition to Nebraska and Colorado, infections have been confirmed in Oregon, Montana, Wyoming, Utah, Kansas, Missouri, Iowa and Wisconsin.
The CDC recommends that anyone who recently ate a McDonald’s Quarter Pounder and is suffering from severe E. coli symptoms — such as bloody diarrhea, a fever of more than 102 degrees, vomiting to the point of being unable to keep liquids down, or signs of dehydration — should contact a medical professional and their state’s health department.
The most common E. coli symptoms include stomach cramps and diarrhea, and they typically start three to four days after ingesting the bacteria. Most people recover without treatment within a week.
People at elevated risk of developing dangerous complications include young children, senior citizens, pregnant women and people with compromised immune systems.
Teresa Murray, consumer watchdog director for the Public Interest Research Group, issued a statement in response to the outbreak calling on food producers, distributors and retailers to do more to protect public health.
Most instances of E. coli contamination are caused by poor sanitation practices, such as employees not washing their hands, crops being grown too close to farms where animals live and contaminate the soil and runoff with feces, and companies’ failure to properly process and test foods, she said.
One of the last major E. coli outbreaks took place in 2015, when contaminated food served at Chipotle Mexican Grill was linked to around 60 cases across the nation, including several in California.
In 2020, Chipotle agreed to pay $25 million to resolve criminal charges alleging that from 2015 to 2018 its contaminated food sickened more than 1,100 people across the United States with pathogens including E. coli, norovirus and salmonella.