Which of the following is NOT a recognized source of Vibrio cholerae?

• A. Contamination of food (vegetables, fish, pork)
• B. Refrigerated, pasteurized dairy products
• C. Night soil fertilizer on veggie crops
• D. Shellfish from coastal estuaries

Answer: (B)

Vibrio cholerae is normally transmitted through ingestion of contaminated water or seafood, and it can also contaminate produce when crops are irrigated with polluted water or fertilized with untreated human waste. Shellfish from coastal estuaries can accumulate the bacteria, making them a common source during outbreaks. Refrigerated, pasteurized dairy products, on the other hand, are not recognized sources because pasteurization kills Vibrio cholerae and refrigeration does not create a favorable environment for its growth. In short, dairy that has been properly pasteurized is not a vehicle for cholera, whereas contaminated vegetables, shellfish from polluted waters, and crops fertilized with contaminated material are potential routes of transmission.