CORE update of October 23, 2024: the CORE list of outbreaks and adverse events includes ten activities, with two new activities. A new outbreak of E. coli O157:H7 (ref #1270) has been added to the table, and FDA has issued an advisory. Most sick people report eating McDonald’s Quarter Pounder burgers. Investigators are working to determine if the slivered onions or beef patties on Quarter Pounder burgers are the likely source of contamination. A new outbreak of Listeria monocytogenes (ref #1268) linked to a not yet identified product has been added to the table. FDA has initiated traceback and an onsite inspection. The outbreak of Salmonella Thompson (ref #1262) linked to a not yet identified product, the case count has increased from 23 to 25 cases. The outbreak of Cyclospora cayetanensis (ref #1245) in a not yet identified product has ended without identifying the product. The outbreak of Cyclospora cayetanensis (ref #1237) in a product that has not yet been identified has ended without identifying the product. @ https://www.fda.gov/food/outbreaks-foodborne-illness/outbreak-investigation-e-coli-o157h7-mcdonalds-quarter-pounders-october-2024