In a kitchen, raw chicken is cut on a board, the board is not washed, and a salad is prepared later on the same board. Which items served as vehicles in this chain and what single immediate action would best prevent transmission?

Only the chicken is the vehicle, while the cutting board plays no role because foodborne pathogens cannot survive on wood or plastic surfaces; therefore refrigerating the salad immediately after preparation is the most effective prevention.

The salad is a mechanical vector because plants actively carry pathogens forward and the proper immediate action is to boil the salad to destroy bacterial life present on vegetables.

The knife pulverizes pathogens making them airborne, so the cutting board is irrelevant and opening windows to increase airflow would be the single most effective prevention against transfer from chicken to salad.

The cutting board and knife are contaminated fomites serving as vehicles; washing and sanitizing the cutting board and utensils between raw meat and produce preparation would best prevent transmission.