On October 23, according to US media reports, on the 22nd local time, the Centers for Disease Control and Prevention (CDC) issued a statement warning that McDonald's "quarter pound burger" has caused E. coli related illnesses in multiple states in the United States.
According to reports, on the same day, the Centers for Disease Control and Prevention stated in a report that 49 people in the United States have fallen ill from consuming "quarter pound hamburgers," with 10 hospitalized and 1 death. Currently, the CDC has launched an investigation into this matter.
The CDC also stated that these patients reported having dined at McDonald's before the onset of the illness, specifically mentioning eating a 'quarter pound burger'.
According to USA Today, cases have also been reported in Colorado and Nebraska, Oregon, and Wisconsin.
The CDC stated that the components of food contamination have not yet been determined. McDonald's stated that preliminary investigations have found that "some patients' illnesses" are related to onion shreds provided by a supplier that serves three McDonald's distribution centers.
McDonald's also stated that it has temporarily withdrawn suspected ingredients related to the accident, and the products involved will not be available for sale in certain states.