Which bacteria is known for causing severe illness and producing Shiga toxin?

The correct choice focuses on E. coli, particularly the strain known as E. coli O157:H7, which is notorious for causing severe illness and producing Shiga toxin. This toxin can lead to serious health complications, including hemolytic uremic syndrome (HUS), which can result in kidney failure. Infection with this bacterium often stems from consuming undercooked ground beef, unpasteurized milk, or contaminated fresh produce.

Understanding the role of Shiga toxin is essential because it can lead to severe gastrointestinal illness, characterized by bloody diarrhea and abdominal cramps. Moreover, the ability of E. coli to produce this toxin sets it apart from other bacteria that typically do not cause the same level of severe illness or complications.

In contrast, the other bacteria listed do not primarily produce Shiga toxin or are not commonly associated with it. Salmonella can cause gastrointestinal illness, Clostridium perfringens typically leads to food poisoning characterized by stomach cramps and diarrhea, and Listeria is known for causing severe infections, particularly in pregnant women, but it does not produce Shiga toxin. Understanding these differences is crucial for food safety and preventing foodborne illnesses.