I know I'm feeding a Troll, but...
I know people with HIV can be kept alive for a long time, but they are obviously infecting other people, because the disease is not going away.
Welcome to 2015.
- A period of time when HIV can be prevented from propagating during sex using an extremely sophisticated method called a "condom".
- A period of time when, at least for the developed world, drugs have advanced to the point where a sick person can be treated and kept alive more or less indefinitely. (although it costs money, and the treatement is a heavy one with some displeasing secondary effect. I would not recommend anyone glossing over "meh, not a problem if I catch HIV, I'll be treated". But I would certainly consider that in the developed world, HIV isn't a deadly disease, merly a chronic one) (that's for the developed world. Poorer region suffer from the fact that drugs cost prohibitively expensive for them and aren't widely available. And also pharma-companies aren't interested in developing cheaper alternatives because they're currently happy with their current earnings, whereas developing cheaper drung doesn't make sens economically to them because they won't recoup the necessary cost from the poorer region).
- A period of time when the drugs have so advanced and are so efficient that, undersome circumstances, it might be possible to reduce the viral load so low that it is almost irrelevant. (These people aren't curred per se. The viral count stay low because they are taking meds. If they stop the virus would rise again. But as long as they keep taking theire meds, virus levels are so low, that from the outside it looks more or less like any random person - including the risks) (again, that's not an excuse to completely forget condoms for ever. But that means, for example, that a man infected by HIV but with a virus level kept low enough, can father a child without risking infecting the mother. And given the preceeding paragraph, that also means that he'll get to see the child birth and see the child grow).
And perhaps if people with deadly diseases can't reasonably be expected to do the right thing on their own,
Right thing on *their* own? You know *YOU* can put a condoms on your dick/a femidom inside your pussy (depending on your sex) if you're so much afraid of catching HIV.
maybe the government should step in and force them to stop infecting healthy humans.
Or you know, maybe encourage *you* to but a condom.
I think I'd rather be killed in a dark alley than find out some girl gave me AIDS. Both are death sentences, but the latter involves years and years of pain and suffering.
Or you know, you could just put a condom on and forget about whole "dying" story.
(Also, you're not going to die of it as of 2015. You'll be on a lot of meds, costing substantial money. But still alive)
Don't engage irresponsible behaviour, use proper protection under all circumstance (except when all people involved have been tested and are known clean).
Depending on availability, either put a condom on (or in, depending on which sets of reproductive organs you happen to be equipped with)
or, when no protection is available, refrain from stick you dick into the pussy (or other similar combination of organs, depending on sex of the person involved) each human being has approximately 2m^2 of skin. Even with only 2 partners, that gives ton of possible combination. Using a bit of imagination, you're bound to find one which doesn't carry an infectious risk and still brings satisfaction to all parties involved.
Also remember: before HIV and AIDS were discovered, nobody knew about risks of AIDS (well, obviously).
But those who used protection (condoms, etc.) where already protected from it even if they didn't knew about it yet. (Maybe they though about avoiding syphilis or ghono. Still that *also* protected them from the yet-unnamed-AIDS).
Same situation now: maybe the person you think engaging sex with hasn't HIV as you think, but maybe the person has some new emerging yet to be formally discovered sexually transmitted disease. If you wear a condom at that moment (on the principle of "always wear one, except with you regular partner once you've both tested") you get automatically protected from the disease even if nobody knows about it yet and no doctor has put a name on it.
A condom is a protection not only against current HIV but against all future STD that might evolve in the future.
(like with HIV), keep them away from other people?
And by the way: "keep the people with HIV away to avoid catching AIDS" in practice boils down to "don't stick you penis inside their pussy" (or other combination of sexual orrifices) and don't mix blood (e.g.: by exchanging used syringes).
That enough to avoid transmitting HIV.
You can eat dinner together, you can drink together, you can work together in the same workplace, ... all 0% risk of VIH infection.
(Well, unless your workplace involves that each work meeting must end up as a giant sex orgy)
(In which case I would totally agree to protect you from your fears and switch jobs with you).