The U.S. Centers for Disease Control on Wednesday identified 15 recent cases of E. coli poisoning linked to onions in Quarter Pounders sold at the quick-food chain.

The cases were from before McDonald’s suspended the use of onions from distributor Taylor Farms’ Colorado Springs facility, the CDC said.

The agency also announced five recent hospitalizations attributed to the outbreak, bringing the total number of hospitalizations to 27 and the total number of cases to 90. One person died in Colorado due to the outbreak

The quick-food giant apologized for the outbreak in an investor call Tuesday, with CEO Chris Kempczinski saying that he was, “relieved that this circumstance appears to be contained and I remain confident in the safety of eating at McDonald’s.”

At least three lawsuits have been filed against McDonald’s in relation to the outbreak, with lawyers for those who have already filed suit anticipating more to arrive.

The corporation announced Sunday that the quarter pounders would profitability within the week.

McDonald’s E. coli case chart

What is E. coli? What are the symptoms?

Most Escherichia coli (E. coli) bacteria reside harmlessly in the intestines of people and animals. But some can factor mild to life-threatening gastrointestinal illnesses if consumed, the CDC says.

The types of E. coli that may factor diarrhea usually spread through food or water contaminated with feces. For instance, food handlers can spread infection when they do not use proper hand washing hygiene after using the restroom. Animals such as cattle may also spread E. coli to food and food crops.

Symptoms of E. coli infection include severe stomach cramps, diarrhea (often bloody), and vomiting, according to the CDC.

The agency recommended seeking immediate medical attention if a McDonald’s customer experiences:

• Diarrhea and a fever higher than 102°F
  • Diarrhea for more than 3 days that is not improving
  • Bloody diarrhea
• So much vomiting that you cannot keep liquids down
• Signs of dehydration, such as:
  • Not urinating much
  • arid mouth and throat
  • Feeling dizzy when standing up