As I continue to work out a few alternate universe ideas for Shadowrun, I came across these pages again:
Sterility Plague
Depopulation Bomb

It occurred to me that this could be an interesting replacement to VITAS. Things would seem far less grim than in canon…at first.

Assume that its symptoms are no worse than a common cold or the flu, so only a small number of very sick or very old people die from it. (Even plain old influenza still has a body count, though it’s not huge.) However, it’s airborne, quite contagious, and has a 50% chance of rendering the victim permanently sterile. More or less everyone will end up catching it eventually, and when they do…flip a coin. Heads they recover from a “24-hour bug” and go on about their lives, tails they also no longer need to worry about birth control.

This kind of thing would be insidious. It would take a while for people to even realize what was going on. It could be a couple of years before teams of virologists all around the world finally conduct their research, write their papers, and hold a press conference to announce their findings. That’s when the real panic starts to hit, and by that point it’s already spread to more or less everyone.

So, there’s no guy pulling a wagon of corpses through the streets, ringing a bell and calling out “Bring out your dead!”, but the end result will still be the same. It’s a slow-motion train wreck that will take decades for its impact to truly manifest upon the world.

And it gets worse. How do you tell that someone’s infertile, if there’s no outward sign? 50% of the world can still have kids, 50% can’t. Of those that can, assume that they’ve got even odds of marrying someone who can’t, and so their potential is wasted. So, you’ve really got only got 25% of the population still having kids. In a few decades that will be a huge geriatric crisis.

It would ultimately serve the same story purpose as VITAS, reducing the future population to early 21st century level, though its mechanism is different and it would take longer to level out.

Let me know what you think.

This sounds like a.lead in to "Handmaid's Tale". There would certainly be 'incentives' to breed.

That's one direction it could go. Children of Men is another, though at 25% it's not quite that bad.

VITAS does more than population reset—it also brings back the idea that it’s normal for young, healthy people to get sick and die in short order on a relatively frequent basis, which is conducive to a general worldview in which life is cheap. Children of Men assumes that we get there through general despair at infertility, but I don’t know if I think that would follow in a less catastrophic fertility crisis scenario.

Worth some pondering, though.

~J

Here's an interesting discussion of the possibility that infertility could be coming in our world:

Scientific American

Check RL birth rates and you'll see there's no need.