A person died and dozens more were infected due to an outbreak of Escherichia coli bacteria, after consuming hamburger meals from the McDonald's chain in several U.S. states, according to the Centers for Disease Control and Prevention (CDC), which announced this on Tuesday.

The health agency clarified that the outbreak, which began in late September, has spread to 10 western states, with most of the 49 cases concentrated in Colorado and Nebraska.

McDonald's shares fell by more than six percent after the announcement.

Ten individuals were hospitalized, including a child suffering from hemolytic uremic syndrome, a serious condition affecting blood vessels in the kidneys.

The CDC indicated the death of an elderly person in Colorado.

The infected individuals reported that they had eaten at McDonald's before the symptoms appeared, specifically mentioning they had the "Quarter Pounder" meal.

While the precise cause of the outbreak has not yet been determined, investigators are focusing on onion slices and beef, which were removed from the affected restaurants during the investigations.

Joe Erlinger, President of McDonald's USA, confirmed in a video message that food safety is a top priority, noting that proactive steps have been taken to remove the onions used in the "Quarter Pounder" meal from certain states, and it was decided to temporarily remove the meal itself from restaurants in the affected areas.

Erlinger added that the majority of states were not affected, and other products, including beef, remain available in the impacted restaurants.

The CDC advised individuals who consumed the "Quarter Pounder" meal and exhibited symptoms of E. coli poisoning, such as diarrhea, high fever, and vomiting, to seek medical attention.

It explained that symptoms typically appear three to four days after exposure, and most patients recover within five to seven days without the need for treatment, although some cases may require hospitalization.