The germ theory of disease is medicine’s main success area. It lead to immunisation and antibiotics. Besides infections, which diseases do we know the true origin of?
Infective, traumatic, toxic and a handful of the population have significant genetic disorders.
These are the only ones we can prevent and we have good methods of treating. We can also treat deficiencies and surgeons can treat regional complaints (eg kidney stones, appendicitis, gallstones- but as we do not know the cause we can’t prevent them).
This is the true irrationality of health- medicine is in such a primitive state that it only knows the origin of about 15% of disease! If that. We don’t know the true origin of cancer, arthritis, asthma, gallstones, kidney stones, appendicitis, diabetes type 1, autism. Much money is used looking for genetic origins, yet it is unlikely they will be found.
Actually I think they are all primarily nutritional in origin- that’s why I’m interested in nutrition!