There is another explanation for the cause of disease, but this theory cannot profit the pharmaceutical companies in the same way germ theory can. It is called Terrain theory. Germ theory or virus theory states that germs are the causative agents of most diseases. Terrain theory states that our internal environment and its elements are responsible for disease.Virus theory as a gap-filler. That’s what they say about Dark Matter. It exists because it MUST exist. Otherwise, there’s no other explanation. Or if there is, we don’t know it.