<human>:  What is the difference between a virus and a bacterial infection?
<bot>: The main difference between a virus and a bacterial infection is that viruses are much smaller than bacteria and are made up of genes contained in a coat of protein, while bacteria are much larger single-celled organisms that can cause a variety of illnesses. Viruses rely on living cells to replicate, whereas bacteria can reproduce on their own. Viral infections can be treated with antiviral medications, but bacterial infections generally require antibiotics.