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You may think of a virus as that nasty illness you get during flu season each year. But actually is a virus? Learn what viruses are made of and how they infect and "reprogram" cells the cells of your body.

About this unit

Viruses: Are they alive? Are they dead? Are they...undead? Learn more about these fascinating (and clinically important) particles that occupy a "gray area" between living and non-living things.