Most bacteria are harmless or even helpful. It helps your body digest food. Fewer than one percent of bacteria cause sickness and disease. Most viruses, on the other hand, cause sickness and disease. Viruses target specific cells in the liver, respiratory system, and bloodstream. Because of their relatively simple structure, they cannot survive without a host. Bacterial infections and viral infections can be almost indistinguishable. They can both present the same symptoms. Doctors use blood and urine tests to determine whether the cause of your illness is viral or bacterial.
Unlike bacteria, antibiotics are not effective against a virus. The most effective treatments for viruses are preventative. Vaccines have reduced the number of viral infections greatly since their development. Doctors use vaccines to combat diseases like polio, measles, and chickenpox.