Overpopulation is not an issue stemming from a lack of disease to kill off people, but stemming from socioeconomic imbalance. The reason why population rates are relatively higher in "third-world" countries is because chances of early death are far higher and wages are much lower; families need to get as many kids out and working as fast as possible just to be able to support themselves. Coupled with traditions of large families and religious that encourage sex for the sake of breeding (as well as some patriarchal societies where men take advantage of women without much if any chance of legal retribution), you have a recipe ripe for lots of child-making. There is a reason Western nations have far lower birth rates: increased socioeconomic stability leads to more personal leisure time available for contemplation of the world, discussion of ethics, etc., leading to increased secularism, as well as much-reduced risk of disease and fatality, and increasingly ego-centric lifestyles. This is a global trend and it is not a coincidence.
So yeah, fuck disease. Contrary to popular belief, most people all feel the same sort of emotions and have the same sorts of revelations and experiences within their lifetimes. It's very easy to think of the masses as a sort of distant phenomenon, but the reality is that there are billions of people in the world who feel and think very similarly to how you do, if not identically. Nobody wants to battle with disease, especially a life-threatening one. It's absolutely unforgivable to deny the ability to live life to its fullest to the world.