Apart from very specific and unfortunate fetishists, no one likes disease. So why don't we just get rid of it all? Let's say you, the Tony Stark of chemists, managed to come up with a pill that eradicates all disease. How much pain would that spare people? What glorious, cough-free fate would you lead mankind to face?
How many centuries would it take for us to grow tired of mocking the anti-vaxxers?
Nim Arinaminpathy, Princeton's mathematical epidemiologist, has actually looked into this, and he's not super sure what would happen if we suddenly gained the ability to wipe away all disease. It would obviously be a positive development for people whose lives are actively ravaged by ailments -- say, the children in Africa who are rendered unable to study and rise out of poverty by constant bouts of malaria. However, it might also accidentally kill off viruses and bacteria that are beneficial to us. That shit has already happened with antibiotics, which wreck the good bacteria in your intestine along with the harmful ones it's supposed to destroy, and our understanding of viruses is still too limited to conclusively determine which of the many ones hitching a ride in our body might secretly be fighting the good fight.
Sure, in the end, Arinaminpathy concludes that eradication of disease would probably be mostly a good thing, because he figures that a whole bunch of the freshly free-of-disease people would be able to get educated, and we'd thus have far more collective brainpower to figure out all the minor kinks that would come with the world's sudden lack of sick days. It's just that not all the kinks would be minor. Here's the world's population growth, complete with estimations up to 2050:
United States Census Bureau
Take a good look at that chart. Rub it on your face, it's fine.