One person has died and dozens have fallen sick following a severe E. coli outbreak linked to McDonald's Quarter Pounder hamburgers, the US Centers for Disease Control and Prevention (CDC) said.
The outbreak, which began in late September, spans ten western states, with most of the 49 cases concentrated in Colorado and Nebraska, the health agency said on Tuesday.
Ten people have been hospitalised, including one child with hemolytic uremic syndrome — a serious condition that damages blood vessels in the kidneys.
"One older person in Colorado has died," a CDC statement said.
All affected people carried the same strain of E. coli and reported eating at McDonald's before developing their symptoms, with most specifically recalling having had Quarter Pounders.
While investigators have not yet pinpointed the exact ingredient causing the outbreak, they are focusing on slivered onions and beef patties — both of which have been removed from restaurants in the affected states pending further investigation.
"Food safety is so important to me and everyone at McDonald's," said Joe Erlinger, president of McDonald's USA, in a video message, offering no substantial response to the outrage beyond this generic statement.
"We've taken steps to proactively remove slivered onions, which are used in Quarter Pounders, in select states.
"We've also made the decision to temporarily remove the Quarter Pounder from restaurants in select states."
Drop in shares
McDonald's shares dropped 9 percent in after-hours trading Tuesday after the CDC's announcement.
The news comes in an already tough year for the Chicago-based McDonald's chain.
Its global same-store sales fell for the first time in nearly four years in the second quarter as inflation-weary customers skipped eating out or chose cheaper options.
Many also launched a boycott against the chain restaurants last year after McDonald's provide thousands of free meals to Israeli soldiers during the Israel's genocidal war in Gaza.
The results of boycott are mostly seen in the Middle East and Asia.