In certain situations, it can taint food, particularly raw meat and vegetables.

CNN: A year later, 'heroic' E. coli survivor still battling

These people almost universally went from a cooked food, meat-centered diet and gave up their meat, their dairy products and their refined sugar and switched to a raw food vegetarian diet, and by simply changing diets their bodies were able to cure their cancer.

FORBES: Connect

Illnesses can be greatly reduced, she said, if food preparers take simple precautions such as washing their hands often and keeping raw meat separate from fruits and vegetables.

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