Which of the following is a human-specific agent that can contaminate food via human waste contaminating the food supply?

• A. Norovirus
• B. Shigella
• C. Campylobacter
• D. Salmonella

Answer: (A)

Norovirus is a human-specific pathogen that readily contaminates food through the fecal-oral route, making it a classic example of contamination arising from human waste. It’s highly infectious—very few viral particles can cause illness—and it spreads easily via infected food handlers, contaminated surfaces, or water, often leading to outbreaks in settings where food is prepared or served by staff. Because it does not rely on animal reservoirs and can persist on hands and surfaces, human waste contamination plays a central role in its transmission.

In contrast, the other organisms are more commonly linked to animal sources or foods associated with animals (like poultry, eggs, or dairy) or to environments where human waste is not the primary driver of transmission, so they don’t exemplify the same human-waste–driven contamination pathway as norovirus.