Identify three major food sources commonly linked to Campylobacter, STEC, and Listeria gastroenteritis.

• A. Campylobacter – undercooked poultry; STEC – undercooked ground beef or contaminated produce; Listeria – unpasteurized dairy products and ready-to-eat deli meats
• B. Campylobacter – undercooked pork; STEC – undercooked chicken; Listeria – canned vegetables
• C. Campylobacter – raw fish; STEC – undercooked turkey; Listeria – pasteurized dairy
• D. Campylobacter – raw eggs; STEC – unpasteurized juice; Listeria – cooked meat

Answer: (A)

The main idea here is which foods are most commonly linked to these three bacteria when people get sick from food. Campylobacter is most strongly tied to poultry, especially when it’s not fully cooked, because the bacteria live in the guts of birds and can contaminate meat during processing. Cooking poultry thoroughly kills the organism, but undercooking or cross-contamination to other foods is a common pathway for illness.

Shiga toxin–producing E. coli (STEC) is classically associated with ground beef that’s not cooked enough, since grinding mixes surface bacteria from the exterior into the interior of the meat. Contaminated produce is another major route, as produce can be tainted by animal feces in the field or during handling, leading to outbreaks even when the beef isn’t involved.

Listeria monocytogenes presents a different risk profile because it can grow at refrigeration temperatures and is frequently found in unpasteurized dairy products and ready-to-eat deli meats. These foods are eaten without a final cooking step, allowing the bacteria to cause illness if present.

So, the combination of undercooked poultry for Campylobacter, undercooked ground beef or contaminated produce for STEC, and unpasteurized dairy products plus ready-to-eat deli meats for Listeria captures the major, well-documented sources of illness for these pathogens. The other options don’t align as closely with the typical, high-risk food sources taught for these bacteria.