ATLANTA — The Centers for Disease Control and Prevention (CDC) released its latest — and likely its last — update on Dec. 3 regarding the E. coli outbreak linked to yellow onions served at McDonald’s restaurants. The agency said it considers the outbreak over and that the US Food and Drug Administration’s (FDA) investigation is officially closed.

The E. coli infections were traced back to onions distributed by Taylor Farms. The company voluntarily recalled its yellow onions and directly notified any foodservice customers who were impacted.

In total, 104 people from 14 states were infected with the E. coli outbreak strain. Of those infected, 34 were hospitalized, and one death occurred.

In the lead up of the investigation, state and local public health officials interviewed affected people about the foods they ate in the weeks prior to getting sick. Out of the 81 people interviewed, 80 (99%) reported eating at McDonald’s, and 75 remembered the specific menu item they ate. Sixty-three people said they ate a menu item containing fresh, slivered onions.

FDA, the Colorado Department of Agriculture (CDA), and Colorado Department of Public Health and Environment (CDPHE) collected several product and environmental samples during the investigation but never discovered a positive match to the strain of E. coli.

One FDA sample of recalled onions and one environmental sample from a grower tested positive for E. coli, but they did not match the outbreak strain or any other clinical illnesses.

According to the CDC, even though the E. coli strain linked to the outbreak was not detected in the samples, epidemiologic and traceback evidence shows that Taylor Farms’ yellow onions were the likely source of the illnesses.

Following the investigation, McDonald’s announced plans to invest $100 million to assist franchisees that were impacted by the outbreak.

Other foodservice operators that sourced onions from Taylor Farms made the decision earlier this fall to pull onions from certain menu items, including Yum! Brands and Restaurant Brands International.