Today there are many ways to treat illnesses. How the disease is treated depends on many factors. First of all, treatment depends on a cause. Many diseases that are caused by bacteria can be treated with a medicine that is called antibiotic. Unfortunately, viruses cannot be treated by antibiotics. The best way to deal with viruses is vaccination.
There are some diseases that require different treatments. For example, if you have chicken pox you will probably be itching. There is no medicine to treat chicken pox, but there are some medicines that can be applied to skin to stop itching. It does not stop the disease but it makes it easier to deal with. In addition, a person could take a pain killer or temperature reducer which will also make them safer and more comfortable until the disease is gone.