Viruses, unlike bacteria, do not multiply on or in food.

This is because they do not have the ability to replicate unless they infect a cell – a living host.  In addition, viruses only infect specific types of host cells, which limits their range.

Question: If viruses do not multiply on food, then how do they cause people to become ill?

Answer: In general, viruses that infect humans come from other humans.  This is very different from bacteria that can come from other animals and virtually any environmental source. Also, they have a low infectious dose – meaning just a few viral particles are necessary to cause an infection.

Question: What is the main reason that viruses cause foodborne illness.

Answer: Not washing hands after using the toilet.

Because viruses do not grow on food, the main way that they cause foodborne illness is when a person has not washed their hands. In fact this is the major cause of all foodborne illnesses!

RECOMMENDED RESOURCES – visit the sites below for more detailed information:

The Bad Bug Book (US Food and Drug Administration) (detailed information)

Common Foodborne Pathogens (Iowa State University (more simplified overview)