Which organism accounted for the largest proportion of raw milk outbreaks (2007-2012)?

• A. Shiga toxin producing E. coli
• B. Salmonella
• C. Campylobacter
• D. Listeria monocytogenes

Answer: (C)

Campylobacter is the organism most often linked to raw milk outbreaks because it commonly resides in the bovine gut and readily contaminates milk during milking. Since raw milk isn’t pasteurized, pathogens like Campylobacter aren’t killed before consumption, making it a frequent cause of illness from these products. In the 2007–2012 period, outbreak surveillance data showed Campylobacter as the leading contributor among raw milk–associated outbreaks. Shiga toxin–producing E. coli and Salmonella do occur in raw milk cases, but not as frequently in these particular outbreaks, and Listeria monocytogenes, while serious, appears less often than Campylobacter in raw milk outbreaks.