E coli Outbreak Linked to McDonald’s Quarter Pounders

Number of sick people by state:

Light green- 1 to 3

Dark green- 4 to 9

Blue- 10 to 26

Image Credits: CDC

An outbreak of Escherichia coli (E coli) O157:H7 infections has been linked to McDonald’s Quarter Pounder hamburgers, prompting health officials to investigate the source of contamination.¹ As of October 22, 2024, there have been 49 cases reported across 10 states, with 10 hospitalizations and 1 death of an older individual with preexisting health conditions in Colorado.²

According to the FDA, Investigators are working to identify the specific source of contamination, focusing on slivered onions and beef patties used in Quarter Pounder burgers. While a specific ingredient has not yet been confirmed, preliminary information suggests that slivered onions may be the likely culprit. In response, McDonald’s has temporarily halted the use of these onions and beef patties in affected states, which include Colorado, Kansas, Utah, Wyoming, and parts of Idaho, Iowa, Missouri, Montana, Nebraska, Nevada, New Mexico, and Oklahoma. Diced onions and other beef patties are not implicated in the outbreak.¹

The CDC, FDA, and USDA FSIS are collaborating on the investigation to confirm the specific contaminated ingredient. There has been no recall issued yet, but the affected hamburgers will not be available in certain locations.³

Statement From McDonald's

In response to the outbreak and ongoing investigation, Joe Erlinger, president of McDonald's USA, issued a public statement emphasizing the company's commitment to food safety. He said, “We are communicating broadly because food safety is so important to me, and everyone at McDonalds. Today, after close consultation with regulatory authorities including the CDC, USDA, and FDA, we’ve taken steps to proactively remove slivered unions, which are used in quarter pounders from restaurants in select states. We also make the decision to temporarily remove the quarter pounder from restaurants in select states.”³

He continued to assure consumers that other menu items, including other beef products in different states, are not affected. He emphasizes that they are working quickly to return to the full menu while taking all necessary precautions, and will continue to keep the public informed with up-to-date information.³

About E coli⁴

Consumers are advised to seek medical attention if they experience severe E coli symptoms, including:

• Severe stomach cramps
• Bloody diarrhea
• Vomiting
• High fever
• Signs of dehydration

Symptoms typically emerge three to four days after exposure, and most individuals recover within five to seven days. However, serious cases can lead to complications requiring hospitalization.⁴

E coli infections can lead to severe health issues, particularly from strains like Shiga toxin-producing E coli (STEC), which may cause diarrhea and serious complications like hemolytic uremic syndrome (HUS). These bacteria are commonly found in the intestines of humans and animals and in food, water, and the environment. While most strains are harmless, some can cause illness through contaminated food or contact with infected individuals or animals. High-risk groups include children under five, adults over 65, and those with weakened immune systems. Proper food handling and hygiene practices are essential for prevention.⁵

Health officials urge the public to stay informed as the investigation progresses and to take precautions while the outbreak's source is identified.

References

1. Outbreak Investigation of E. coli O157:H7: McDonald’s Quarter Pounders (October 2024). FDA. October 22, 2024. Accessed October 23, 2024. https://www.fda.gov/food/outbreaks-foodborne-illness/outbreak-investigation-e-coli-o157h7-mcdonalds-quarter-pounders-october-2024

2. State health department coordinating with CDC as it warns of E. coli associated with McDonald’s locations. CDPHE. October 22, 2024. Accessed October 23, 2024. https://cdphe.colorado.gov/press-release/state-health-department-coordinating-with-cdc-as-it-warns-of-e-coli-associated-with

3. McDonald's issues statement following deadly E. coli outbreak. October 22, 2024. Accessed October 23, 2024. https://www.wlbt.com/video/2024/10/22/mcdonalds-issues-statement-following-deadly-e-coli-outbreak/

4. E. coli Outbreak Linked to McDonald’s Quarter Pounders. CDC. October 22, 2024. Accessed October 23, 2024. https://www.cdc.gov/ecoli/outbreaks/e-coli-O157.html

5. About Escherichia coli Infection. CDC. May 14, 2024. Accessed October 23, 2024. https://www.cdc.gov/ecoli/about/?CDC_AAref_Val=https://www.cdc.gov/ecoli/general/index.html