Chicago-area hospitals on alert for E. coli symptoms amid outbreak tied to McDonald's

CHICAGO (WLS) -- The head of McDonald's is reassuring customers Wednesday that it's safe to eat at its restaurants despite a deadly E. coli outbreak.

ABC7 took a closer look at E. coli, the symptoms and why the outbreak could be more widespread than what's been reported.

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At least 49 people have gotten sick in 10 states, including Wisconsin. One person has died and 10 people have been hospitalized. The likely source of the contamination is slivered onions served on the Quarter Pounder. McDonald's has removed the burger from its menu in impacted states.

Northwestern Medicine's Urgent Care center on Dearborn has not seen any patients sick from the recent McDonald's E. coli outbreak, but the staff is aware.

READ MORE | 1 dead in multistate E. coli outbreak tied to McDonald's Quarter Pounders, CDC says

"It's certainly something we need to know about it, so I would recommend getting tested if you are worried about it and there has been a possible exposure," Northwestern Medicine Immediate Care Physician Dr. Tyler Egbert said.

Dr. Egbert said the symptoms of E. coli and other gastrointestinal illness like listeria can be similar with bouts of diarrhea, nausea and even fever. For those who are well enough to stay home, he said hydration is key to getting better. However, E. coli can have long term and even deadly consequences, so he urges vigilance.

"If you notice you are developing signs of dehydration, feeling really dry, hard to get up, developing weakness, dizziness, light headedness, ongoing fevers, then you definitely come and need to get checked out," Dr. Egbert said. "Call your doctor. Go to immediate care. If it's severe, go to the emergency rooms."

Dr. Emily Landon at UChicago Medicine is an infectious disease specialist.

"This is a fast-moving situation and a fast-moving bacteria," Dr. Landon said. "You get sick pretty fast after eating it, so my guess is that [cases] they will spike up and then come down."

The CDC reports, "the true number of sick people in this outbreak is likely much higher than the number reported, and the outbreak may not be limited to the states with known illnesses."

Dr. Landon expects the number of cases from this most recent outbreak to increase.

"We often end up under counting the total number, because only the people who are sick enough to to get medical care actually get tested," Dr. Landon said.

Health experts urge people who are very young, over 65 or have compromised immune systems to seek medical attention if symptoms persist.