When People Got Sick: E. coli Outbreak, Onions Served at McDonald's - November 13, 2024

Key points

Epidemiologic and traceback data show that fresh, slivered onions served at McDonald’s were the likely source of this outbreak. Affected onions served at McDonald's locations were recalled and are past shelf life.

McDonald's Quarter Pounder with cheese on a white background

When people got sick

This chart shows when the 104 people in this E. coli outbreak got sick.

Recent illnesses may not yet be reported as it usually takes 3 to 4 weeks to determine if a sick person is part of an outbreak. The true number of sick people in this outbreak is also likely much higher than the number reported. This is because many people recover without medical care and are not tested for E. coli.