Ironically, one of the world's most highly treated diseases is also one of the leading infectious-diseases today. It is tuberculosis, and its being highly deadly despite it being easily treated is often related to poverty as people who are below the poverty line are most likely exposed to TB-inducing environments and add to that the lack o access to medicine.
In some countries, treatment to this disease is given for free but lack of information dissemination is still a hindrance. Unfortunately, southern Chile is still TB-infected.