E. coli O157:H7 illness is most often linked to which category?

• A. Beef
• B. Vegetable row crops (leafy greens)
• C. Dairy
• D. Seafood

Answer: (A)

Beef products, especially ground beef, are the most common vehicle for E. coli O157:H7 illness because cattle can carry the bacteria, and grinding meat distributes any surface contamination throughout the product. When ground beef is undercooked, the bacteria can survive inside the patty and be ingested, leading to illness. That’s why cooking ground beef to a safe internal temperature (about 160°F/71°C) is emphasized to prevent these infections.

Dairy, leafy greens, and seafood can also cause E. coli illness, but outbreaks linked to beef—particularly ground beef—historically occur more frequently. Produces outbreaks have grown in prominence in recent years, but the overall pattern has long shown beef as the primary source.