The E. Coli outbreak linked to McDonald’s is expanding, now affecting 13 states, including Iowa

CEDAR RAPIDS, Iowa — A deadly outbreak of E. coli infectionsnow spreading to 13 states, has been linked to McDonald’s Quarter Pounder burgers, with at least 75 people sickened, including one confirmed case in Iowa.

Federal health officials, including the Centers for Disease Control and Prevention (CDC) and the Food and Drug Administration (FDA), identified raw sliced ​​onions on these burgers as a possible source of contamination, prompting a recall from Taylor Farms, the supplier Onion McDonald’s.

“This is not the usual E. coli that you look for in beach water, which indicates fecal contamination,” said Dr. Michael Pentella, clinical professor of epidemiology and director of the State Hygiene Laboratory at the University of Iowa. According to Pentella, this strain, E. coli O157, is “a very specific type of E. coli that produces this toxin,” a shiga toxin that leads to gastrointestinal upset and can escalate to a potentially fatal condition known under the name hemolytic. uremic syndrome (HUS).

“You see blood in the stool and you can have very severe systemic disease,” he explained, adding that patients with HUS are often hospitalized and can suffer lasting complications or, in rare cases, death. The CDC has confirmed that two people have developed HUS from this outbreak and 22 people have been hospitalized. In Colorado, where the largest number of cases have been reported, one person has died.

The ages of those infected vary between 13 and 88 years. “People have an incubation period of about one to 10 days,” Pentella said, complicating efforts to track recent exposures because symptoms can appear up to a week after eating contaminated food.

The rapidly spreading outbreak has prompted immediate action by companies and consumers. McDonald’s has suspended sales of Quarter Pounders in affected areas, including parts of the Midwest and Mountain West. Other national chains, including Taco Bell, KFC and Burger King, which sourced their onions from Taylor Farms, voluntarily pulled fresh onions from certain stores. “Restaurants are inspected by local health departments,” Pentella said, “and so a restaurant that has an outbreak associated with it will do everything they can to prevent further cases.”

Taylor Farms, which supplies onions to McDonald’s and other restaurant chains, issued a voluntary recall of the affected products following CDC recommendations. “If those onions are contaminated and not cooked, they can contain that organism,” Pentella said, explaining that raw foods like onions pose a greater risk than cooked foods. He recalled similar outbreaks in the past. “You may recall a few years ago, we had a lettuce outbreak of E. coli 157 that was associated with lettuce that had been irrigated with contaminated water.”

The E. coli strain O157 has a history of triggering high-profile outbreaks. In the 1990s, an E. coli outbreak on the West Coast led to severe illness and regulatory changes that instituted new standards for cooking hamburger meat. “That led to requirements for treatment, to cook the hamburger meat better by cooking the food well, you kill that organism,” Pentella said. However, this current outbreak, he noted, may not be solved by cooking precautions because “onions are not always cooked before they are ingested.”

Dr. Pentella advises consumers who experience symptoms such as severe stomach cramps, diarrhea, especially if bloody, vomiting or signs of dehydration to seek medical attention.

“The most important thing anyone can do,” Pentella advised, “is when they have a foodborne illness, call the health department.” In Iowa, residents can contact the state Department of Health’s hotline at 1-800-362-2736.

This outbreak also had financial implications, with McDonald’s stock plummeting following news of the E. coli cases. Shares fell 5 percent in Wednesday trading and another 3 percent on Friday as investors expressed concern about potential legal and regulatory fallout. Lawsuits have already been filed by affected individuals, including a Colorado resident who claims he was infected after eating a quarter pounder. The lawsuits allege that McDonald’s failed to take adequate precautions to prevent contamination.

Dr. Pentella pointed out that foodborne illnesses, such as those caused by E. coli, norovirus and salmonella, occur frequently in all types of dining experiences. “The risk of getting a foodborne illness is no greater from a fast food restaurant than from cooking at home,” he said. He recommends basic safety practices such as washing hands and kitchen surfaces, storing food properly, and making sure refrigerators are kept at 40F or lower to prevent bacteria growth.

The epidemiologist stressed that while McDonald’s and public health officials work to identify the source of the contamination, food safety measures are essential in both public and private settings. However, he acknowledged that contamination can occur at any point in the food supply chain, from production to preparation.

This investigation remains ongoing, with the CDC reporting that additional cases may be linked as health officials piece together the route of contamination. In the meantime, Dr. Pentella’s advice to the public is to be cautious, but not to panic. “Just remember that about 50 million people in the U.S. experience foodborne illness every year,” he said, adding that many cases arise from food prepared at home, underscoring the importance of food safety everywhere.

“I wouldn’t hesitate to go to McDonald’s today, personally,” he said, noting that McDonald’s response to the outbreak and food safety protocols are robust.