At least 75 people are sick in 13 US states after McDonald’s was rocked by a deadly outbreak of E. coli in is quarter pounders.
Billions of dollars were wiped off the fast-food giant’s value.
A total of 22 people are hospitalised and two have developed a dangerous kidney disease complication, the Centres for Disease Control and Prevention said.
One woman died in Colorado, according to reports.
No definitive source of the poisoning has in hamburgers been identified, officials with the US Food and Drug Administration said.
Early analysis by the FDA showed that uncooked slivered onions used on the burgers “are a likely source of contamination,” the agency added.
McDonald’s stores in the UK and Ireland have not been affected.
Taylor Farms, a California-based produce company, was the supplier of fresh onions used in restaurants involved in the outbreak.
The vegetables had come from a facility in Colorado Springs, Colorado.
“We have made the decision to stop sourcing onions from Taylor Farms’ Colorado Springs facility indefinitely,” McDonald’s said in a statement released late on Friday.
Taylor Farms said it had pre-emptively recalled yellow onions sent to its customers and continues to work with the CDC and the FDA as they investigate.
McDonald’s pulled quarter pounders from menus in several states - mostly in the Midwest and Mountain states - when the outbreak was announced Tuesday.
On Friday, it said that slivered onions were distributed to approximately 900 of its restaurants, including some airports.
The new cases reported were a sharp increase from the original tally of 49 in 10 states.
Most illnesses were reported in Colorado, with 26 cases. Around 13 people were sick in Montana, 11 in Nebraska, 5 each in New Mexico and Utah, 4 each in Missouri and Wyoming, two in Michigan and one each in Iowa, Kansas, Oregon, Wisconsin and Washington, the CDC reported.
Several other fast-food restaurants - including Taco Bell, Pizza Hut, KFC and Burger King - pulled onions from some menus in certain areas this week.
McDonald’s market value has fell to about $215 billion (£166 billion) from over $225 billion (£174 billion) on Tuesday.
Receptionist Clarissa DeBock, 33, is one of several people planning to sue them, according to court records.
According to her lawsuit, she ate food from a restaurant in Nebraska on September 18, fell ill days later and sought emergency care before being diagnosed with an E. coli infection.
Symptoms of poisoning can occur quickly, within a day or two of eating contaminated food. They typically include fever, vomiting, diarrhoea and signs of dehydration.
McDonald’s USA president Joe Erlinger told NBC: “We are very confident that you can go to McDonald’s and enjoy our classics.
“I want to say to our consumers that you can confidently go to McDonald’s today.
“If there has been contaminated product within our supply chain, it’s very likely worked itself through that supply chain already.”
