An E. coli outbreak linked to McDonald’s has prompted the fast food chain to pull specific ingredients and its Quarter Pounder hamburgers in several locations. The outbreak is currently under investigation by multiple federal and state agencies. Here is everything known to date about this large-scale incident:
Background
The Centers for Disease Control and Prevention (CDC), along with the Food and Drug Administration (FDA) and the U.S. Department of Agriculture’s Food Safety and Inspection Service (FSIS), are working to identify the specific contaminated ingredient causing the E. coli O157:H7 infections. Most affected individuals reported consuming McDonald’s Quarter Pounders before falling ill.
In response, McDonald’s has taken precautionary measures and has temporarily suspended the use of two ingredients: fresh slivered onions and quarter-pound beef patties in affected regions. The quarter-pound beef patties are exclusively used in Quarter Pounder hamburgers, while the fresh slivered onions primarily appear in this menu item and rarely in other offerings.
The CDC said that McDonald’s is cooperating with investigators to identify the contaminated ingredient.
The outbreak’s scope has led to the temporary unavailability of Quarter Pounders in several states.
November 13, 2024 Update
- A total of 104 people, an increase of 14 from the previous October 30, 2024 update, and over double the 49 initially announced cases, have now been infected with the outbreak strain of E. coli O157:H7 across 14 states, up from the previously announced number of 13 states.
- 34 people have been hospitalized, an increase of 7 from the previous October 30, 2024 update, and over three times the initially announced 10 hospitalizations.
- 4 people have developed hemolytic uremic syndrome (HUS), a severe infection of the kidneys that can be life-threatening, up from the two reported cases of HUS from the previous October 30, 2024 update.
- 1 person has died in Colorado but not from HUS. There have been no new deaths attributed to this outbreak.
- Additional cases of illness have surfaced, but these occurred before McDonald’s and Taylor Farms acted to pull slivered onions from restaurants.
- Of the 81 people interviewed so far, all but one have reported eating at McDonald’s.
- 75 people remembered the specific items they ate at McDonald’s.
- 63 of 75 people reported consuming an item that contained fresh slivered onions.
- Health authorities including the FDA and Colorado state agencies have been investigating onions connected to McDonald’s locations and related facilities through laboratory testing. While they found one sample of recalled onions that tested positive for E. coli, it was identified as type O168:H8 with the stx2a gene – a different strain than the one causing the current outbreak. Although this sample contained Shiga toxin-producing E. coli (STEC), it hasn’t been linked to any reported illnesses. The investigation is ongoing, with more test results still pending and updates to follow.
- Inspections by the FDA at a Taylor Farms processing facility in Coloardo and an onion farm in Washington state have been completed.
- In response to the outbreak, McDonald’s temporarily removed slivered onions from Quarter Pounders in affected regions until they could secure a new supplier, and has since resumed using onions from this alternative source.
- Taylor Farms issued a recall of their yellow onions on October 22, 2024, alerting their food service clients to stop serving these products. While the FDA continues to work with Taylor Farms to assess if additional recalls are needed down the supply chain, the recalled onions should not be available in retail stores, and food service businesses have been instructed to halt distribution.
- Current evidence suggests that the outbreak risk at McDonald’s restaurants has been resolved.
- Any affected onions have been recalled from McDonald’s locations and are past their shelf life.
Timeline – November 13, 2024 Update
The first reported case of illness linked to this outbreak was on September 27, 2024 and the last reported onset of illness was on October 21, 2024.
Location of Affected Individuals – November 13, 2024 Update
- Washington, Oregon, Kansas, Iowa, Wisconsin, Michigan, North Carolina – 1 to 5 sick people
- Wyoming, Utah, New Mexico, Nebraska, Missouri – 6 to 15 sick people
- Colorado, Montana – 16 to 30 sick people
- 104 total illnesses to date
The CDC said that the actual number of impacted individuals is likely much higher than the number reported so far because many people will recover without medical intervention or do not get tested for E. coli infection. Additionally, the agency said that “recent illnesses may not yet be reported as it usually takes 3-4 weeks to determine if a sick person is part of an outbreak.”
Demographics – November 13, 2024 Update
The CDC said that officials collect a variety of demographic data from affected individuals during an outbreak of foodborne illness to help determine the source of the infection.
| Demographics | Information |
| Age (information from 104 people) | Ranges from 1 to 88 years old Median age of 28 years old |
| Sex (information from 104 people) | 40% female 60% male |
| Race (information from 96 people) | 95% White 2% Black 1% Native American or Alaska Native 0% Asian 0% Native Hawaiian or Pacific Islander 2% reported more than one race |
| Ethnicity (information from 93 people) | 89% non-Hispanic 11% Hispanic |
Suspected Source
Although potentially contaminated beef was also initially suspected, federal and state health agencies are now working to determine if adulterated onions are the source of the outbreak. Traceback analysis is still being conducted on the ground beef patties served at McDonald’s restaurants as a source of the illness.
The FDA’s initial traceback and distribution data suggest that slivered onions used on Quarter Pounders are a probable source of contamination. The FDA is actively working to verify if these onions are indeed linked to the outbreak and to identify whether they were also used or sold by other establishments.
Taylor Farms, which supplies sliced onions to the affected McDonald’s locations, has voluntarily recalled their products. The company has also notified other food service customers who received the potentially contaminated onions.
The FDA, USDA Food Safety and Inspection Service, and CDC are collaborating to trace the contamination source through distribution records and product sampling.
Lawsuits
Two lawsuits have already been filed against McDonald’s in the Circuit Court of Cook County, Illinois by Houston, Texas-based Ron Simon & Associates, a national food safety law firm.
The first E. coli McDonald’s lawsuit was filed on Wednesday, October 23, 2024, on behalf of Eric Stelly, a Colorado resident who ate at a local McDonald’s restaurant on Friday, October 4, 2024. Two days later, Stelly began experiencing symptoms of food poisoning, including bloody stools, a common symptom of E. coli poisoning.
Stelly’s lawsuit presents three main claims against McDonald’s, including strict products liability, negligence and negligence per se, and breach of implied warranties.
The second lawsuit against McDonald’s was filed on Thursday, October 24, 2024 on behalf of Clarissa DeBock, a Nebraska resident who ate at a local McDonald’s restaurant on September 18, 2024. By September 23, DeBock was experiencing severe food poisoning symptoms and had to see medical care. While being treated, hospital staff diagnosed DeBock with an infection of E. coli.
Both lawsuits claim Stelly and DeBock were injured and that McDonald’s is responsible for the damages caused, including pain, suffering, medical costs, emotional distress, lost wages, and other related expenses, both past and future.
On Monday, October 28, 2024, Ron Simon & Associates issued a press release that the firm was now representing over three dozen families affected by the McDonald’s E. coli outbreak, including three cases of Hemolytic Uremic Syndrome (HUS).
More lawsuits are expected to be filed against McDonald’s in the coming days and weeks.
Health Risks
This outbreak is particularly concerning due to its rapid spread across multiple states and the severity of cases, including one death. E. coli O157:H7 is a particularly dangerous strain of bacteria that can cause severe illness, especially in vulnerable populations such as the elderly, young children, and those with compromised immune systems.
The majority of E. coli strains are not harmful and play a crucial role in maintaining a healthy gut ecosystem by assisting in breaking down the food, contributing to the production of essential vitamins, and acting as a defense mechanism against more dangerous microorganisms.
However, not all E. coli are benign. Certain strains can cause a range of health issues in humans, including gastrointestinal distress resulting in diarrhea, infections of the urinary tract, respiratory ailments like pneumonia, systemic infections such as sepsis, and hemolytic uremic syndrome (HUS) – a potentially deadly complication that can severely damage the kidneys and other vital organs. Those infected with E. coli usually exhibit symptoms within 3 to 4 days after ingesting the bacteria.
Consumer Action
The CDC has asked consumers to contact their healthcare provider if they ate a McDonald’s Quarter Pounder hamburger and are experiencing severe E. coli symptoms:
- Diarrhea and fever higher than 102°F
- Diarrhea for more than 3 days that is not improving
- Bloody diarrhea
- So much vomiting that you can’t keep liquids down
- Signs of dehydration:
- Limited urination
- Dry mouth and throat
- Feeling dizzy when standing up
Commercial Action
The CDC has asked that any business in possession of the recalled yellow onions from Taylor Farms to not sell, eat, serve, or further distribute them.
What’s Next
The CDC has said this is a fast-moving investigation and already provided its second update three days after the initial announcement on October 22, 2024. It is expected that the organization will continue to provide timely updates, especially as it attempts to uncover the source of the outbreak.
Commenting on this article, one national E. coli lawyer said, “An E. coli infection has the potential to be extremely dangerous, especially if it develops into Hemolytic Uremic Syndrome, or HUS. I strongly urge any consumer who exhibits signs of E. coli infection to contact their medical provider immediately.”
