Could it have been prevented... Hmmm.
Depends on which side of the theory you fall on. If you, like many others, believe that HIV/AIDS was cooked in a laboratory and purposefully released into the wild... then yes it could have been prevented.
If you like the rest of the crowd out there actually believe that the green monkey passed on HIV/Aids to humans in natural ways, then most likely no it could not have been prevented.
Could we have slowed the progression? Sure. Its not airborne.... yet.
While I hate to bring the subject up because it was so controversial back in the day, rounding up the infected and putting them in quarantine was actually the better idea. Human rights and all of those 'morality issues' people had did nothing to slow or halt the spread of HIV.
Just one more case which demonstrates that humans reacting with their emotions doesn't end well.
We all know how HIV/AIDS is contracted - we all know that wearing a condom greatly reduces potential to spread this (and other) infection(s). We also know that promiscuity leads to greater risks of contracting than monogamy, we all know that no sex at all means no STD at all.
Yet still we have people who partake of all of the wrong things that leads to the spread of this and every other STD.
Apparently humans are hardwired to not be safe, therefore I submit that preventing the spread of HIV or any other STD is an exercise in futility. Humans can't control themselves.
As I recall it didn't take long for the whole LGBT community to know that HIV/AIDS was out there. But even as late as the 1990's people flat refused to wear condoms. Even having people like myself going from bar to bar handing out literature and condoms still lead to the spread of HIV and other STDS. We did slow it slightly - but in the end it was an exercise in futility because now we have this generation that views HIV/AIDS as a treatable condition thus its not that big of a deal to worry about.
Personally, I think coming up with a treatment was the worst possible thing we could have done. Scientists should have lied through their teeth and say its untreatable while continue working on a cure just to scare the bejesus out of everyone which would have worked far more efficiently to slow the progress of this particular virus.
Sure, people would have died - however less people would be infected today. The fear of death lead to our generation being a wee bit more safe and sane in bed than today's generation.
Fear is a powerful motivator, today in the western world there is insufficient fear of the virus which is leading to its spread which is leading to more mutations which will lead to an airborne variety arising eventually. Or a non treatable variant or one that spreads like wildfire, or some other horrific mutation.
Understand I watched many people die from this virus. My brother died from it, after losing his eyeballs, after dementia set in, it was a horrific way to go. However with it being such a horrific way to go many guys thought twice before engaging in unsafe sex which lead to less spread of infection.
Today the horror of HIV is being stuck on a drug for the rest one one's life and suffering the minor side effects of the drugs... Well aside from the other psychological issues which people deny and swear ain't really there.
Human nature being what it is, the spread of HIV is what it is - and I seriously doubt that it could have been prevented, slowed, or reduced because humans are unable to do the right things.