“It is more important to know what sort of person has a disease, than to know what sort of disease a person has.” - Hippocrates
Western medicine has focused on the Germ Theory of disease for the past 150 years. In this model, infecting microbes (viruses, bacteria, fungi, parasites, and other pathogens) is defined as the cause of illness.
If you kill the germs you avoid or cure the diseases they produce. The idea is that germs are bad and that they are the cause of dise