We completely screwed natural selection, so I guess bad genes will be creeping into the population for a long time, things like cancer, malformations and genetic related diseases will be blooming like crazy in the next centuries.
Let's hope medicine keeps up with it.
Almost all diseases that happen after a species' reproductive age is very difficult to select out either in a positive or negative way unless it happens to be strongly genetically linked (either through sharing genes or being very close on a chromosome) to a different positive or negative trait. Even then in the long run the survival of that trait will be dominated by its independent characteristics.
The way to flip this around is that you could also look at the "survival" of the disease, disorder, etc. Not that we WANT these to survive, but they either will or won't. If a disease causes death 100% of the time at age 2 and provides no other benefits in the carrier / recessive trait it tends not to last in the gene pool for very long.
Well that's not entirely true. I think humans evolved (and still evolve) on a tribal level. So an individual's traits that strengthen the tribe are also good for the survival of the tribe since one's entire gene pool would be wiped if the neighboring tribe killed all of you, even if the individual is post-reproductive age. I find that most people never talk about evolution on a tribal level like this.
So once genetic desease reaches a problematic threshold (where medicine can not offset it), I'm pretty sure people will begin to talk about their families health history earlier in the mating ritual.
Or test (and select) their embryos if the bad trait was passed on. Or at some point modify them. Which both will lower the spread of bad genes.
it's too simple to regard evolution as something that happens merely on an individual level. e.g. it was always possible that the strongest and smartest human will get killed by a group of physically and intellectually weaker people. does that mean we stopped evolving back then? no, we evolved social behavior, like many animals before us, i guess...