I can give you many counter examples, such as hepatitis C, that were previously incurable or hard to cure. For some diseases we have managed to get a sterilizin

I can give you many counter examples, such as hepatitis C, that were previously incurable or hard to cure. For some diseases we have managed to get a sterilizing (=complete) cure, for some others (like HIV) a functional cure (=you live long and healthy even though the virus is still in your body). In part, it is a function of cost allocation.