Health officials are investigating an E. coli outbreak connected to McDonald’s Quarter Pounder burgers, affecting at least 49 people in 10 states, according to the Centers for Disease Control and Prevention (CDC). The outbreak has led to one death in Colorado and 10 hospitalizations, including a child who developed hemolytic uremic syndrome, a serious kidney condition.
The exact cause of the outbreak is still unclear, but slivered onions and quarter-pound beef patties used in the burgers are under scrutiny. McDonald’s has stopped using these ingredients in several states while cooperating with public health authorities.
The first case was reported on September 27, with state health officials in Colorado alerting the CDC on October 10. The investigation officially began on October 15. While the risk to the public is now considered low, the CDC anticipates more cases to emerge as not all have been reported yet.
The U.S. Food and Drug Administration (FDA) and the Department of Agriculture are assisting in the investigation, focusing on whether the onions may have been distributed to other businesses.