McDonald's E. coli outbreak is over, CDC says

The E. coli outbreak linked to slivered onions on McDonald’s Quarter Pounder hamburgers is over, the Centers for Disease Control and Prevention said Tuesday.

Since the investigation began Oct. 22, 104 cases of E. coli in 14 states were identified. Thirty-four people were hospitalized, and one person, an older adult in Mesa County, Colorado, died.

California-based Taylor Farms distributed the onions linked to the outbreak and served at McDonald’s restaurants in several states, according to the Food and Drug Administration. A McDonald’s spokesperson said that all Quarter Pounders were pulled from the restaurants in the 14 states when the outbreak was announced in October.

At least four people developed a serious illness that can lead to kidney failure, called hemolytic uremic syndrome. One of those patients was a 15-year-old girl from Grand Junction, Colorado, her family told NBC News.

The high school freshman’s initial symptoms — fever and stomach pain — began just days after she visited McDonald’s several times for her favorite meal: a Quarter Pounder with cheese and extra pickles. Her illness worsened with vomiting and bloody diarrhea.

While many strains of E. coli bacteria are mostly harmless, eating food or drinking water contaminated with certain strains can lead to major gastrointestinal problems.

Investigators interviewed most of the people who got sick and linked their illnesses to Quarter Pounders.

Nearly all of the 81 people interviewed said they’d eaten at McDonald’s. Most of those people, 63, said their food contained fresh, slivered onions. The Quarter Pounder is the only menu item that contains those specific onions.

Quick recall of the onions appears to have resolved the outbreak.

“There does not appear to be a continued food safety concern related to this outbreak,” the FDA said in a news release Tuesday. “CDC considers this outbreak over, and FDA’s investigation is closed.”