What are Shiga toxin-producing strains of Escherichia coli?
Escherichia coli (E. coli) is a bacterium. Although most strains of this bacterium are harmless, some strains produce a powerful toxin that can cause illness. These strains are called Shiga toxin-producing E. coli (STEC). The most common STEC strain in North America is E. coli O157:H7. Where are STEC bacteria found? STEC bacteria are normally found in the intestines of cattle; however, other animals such as deer may also carry STEC. How do these bacteria spread? Because these bacteria are normally found in cattle, contamination of meat (especially ground beef) may occur during the slaughtering process. Eating contaminated meat that has not been thoroughly cooked can cause illness. In addition, outbreaks have been associated with consuming raw milk, unpasteurized apple cider, contaminated water, sprouts, lettuce, salami, and venison. Transmission also occurs directly from person-to- person, especially in families and in high-risk settings like daycare centers. Who gets STEC infections?
