McDonald’s is facing a serious situation as an E. coli outbreak has been linked to its popular Quarter Pounder burgers. This news has caused the company’s shares to drop significantly in after-hours trading. Here’s what you need to know about the outbreak and its impact on the fast-food giant.
E. Coli Outbreak Details
The Centers for Disease Control and Prevention (CDC) reported that the outbreak has resulted in 49 cases across 10 states between September 27 and October 11. So far, there have been 10 hospitalizations and one reported death in Colorado. Most sick individuals indicated they had eaten a Quarter Pounder.
One patient even developed hemolytic uremic syndrome, a severe condition that can lead to kidney failure.
Share Price Reaction
Following the CDC’s announcement, McDonald’s shares fell about 7% in extended trading on Tuesday. This decline highlights the immediate financial impact of the health scare on the company.
Company Response
In a statement, McDonald’s emphasized its commitment to food safety and said it is taking “swift and decisive action.” The initial investigation suggests that slivered onions, used in the Quarter Pounders and supplied by a single supplier, may be the source of the outbreak.
As a precaution, McDonald’s has instructed restaurants in the affected areas to remove these onions from their supply and has temporarily halted distribution. Quarter Pounders will also be unavailable in several Western states, including Colorado, Kansas, Utah, and Wyoming.
Other Menu Items Unaffected
Joe Erlinger, President of McDonald’s USA, reassured customers that the majority of menu items remain safe. Other beef products like the Big Mac and cheeseburgers use a different type of onion and are not linked to the outbreak.
“We are working quickly to return our full menu in these states as soon as possible,” Erlinger stated.
CDC Warnings and Symptoms
The CDC has warned that the actual number of affected individuals could be much higher than reported, as many may recover without testing. E. coli infections can cause symptoms like stomach cramps, diarrhea, and vomiting, typically starting three to four days after exposure.
While most people recover without treatment within a week, the severity of the outbreak has raised concerns.
Past E. Coli Incidents
This isn’t the first time McDonald’s has dealt with E. coli cases. In 2022, several children in Alabama became ill after consuming Chicken McNuggets from Happy Meals, with four needing hospitalization.
As the situation develops, McDonald’s is working hard to address the issue and reassure customers about the safety of its food.

I am Aparna Sahu
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