A virus is non-living and cannot be treated by antibiotics, they do not have a cell wall. Viruses are generally smaller and require a host to survive. A bacteria can be affected by antibiotics and can survive outside of a host. Bacteria can be free-living and do not require a host to reproduce. An example of a virus would be the Herpes virus (Herpes simplex). An example of a bacteria would be MRSA (An antibiotic strain of Staphylococcus aureus).