The difference between bacteria and viruses is mainly in the size, structure and medication used to treat the infection. 1. Size: Compared with bacteria, viruses are a little smaller. Bacteria are generally measured in micrometers, which can be seen with an ordinary light microscope, while viruses are generally measured in nanometers or millimeters, which can not be observed with an ordinary light microscope, and must be observed with an electron microscope. 2. Structure: bacteria have a complete structure, including the cell wall, cell membrane, cytoplasm and nucleoplasm, belonging to the unicellular organisms. Viruses do not have a cellular structure, mainly composed of internal nucleic acids and external protein shells, and must rely on cells to survive, there is no independent ability to survive. 3. medication: anti-bacterial drugs and anti-viral drugs can not be used interactively, bacterial infections with anti-bacterial drugs, such as penicillin, cephalosporin, etc., viral infections with anti-viral drugs, such as entecavir, oseltamivir and so on. If infected with bacteria to develop good personal hygiene habits, pay attention to dietary hygiene, diligent disinfection, sterilization, can effectively prevent infection with bacteria or viruses. If bacterial or viral infection occurs, you should seek medical advice promptly to avoid aggravation of the condition.