There are various ways to protect yourself (PrEP, condoms). Both are about 98% effective when all directions are followed. But in real life, people are inconsistent - they use condoms incorrectly, and they sometimes forget to take their pills. So the real life stat is more like 90% in actual observed studies with actual people.
But you are asking about the alternative of completely unprotected sex. And I have to ask - why? What is the benefit you want to gain from not having any protection? Because whatever that benefit is, you have to weigh it against the risk of giving or receiving an incurable, life-altering, potentially deadly disease. That is the bottom line.
I realize that can seem abstract today - the ravages of the disease aren't in-your-face the way it was in the 80s and 90s. People no longer have to go to a funeral a week. The obituaries in the gay press are no longer 20 pages long.
But HIV itself hasn't changed and the way its transmitted hasn't changed and once you have it there is still no way back to "normal". You will have to manage it the rest of your life, and lord help you if you lose your insurance or can't pay the premiums or co-pays for your meds.
I run projects for a living and one of the things we do all the time is evaluate risks. There are two things that identify a risk:
- How likely will it happen?
- How destructive will the consequences be if it does happen.
A fire is something that is rather common, so it is a risk we would plan for. An earthquake is uncommon, but because it could potentially destroy all the infrastructure, the consequences are so great that we would be wise to make a plan to recover if it occurs.
HIV infection is, unfortunately, both very common in gay men and irreversibly destructive - potentially fatal. That makes it a high risk that you want to prevent from happening if at all possible.
You might say, "But I'm just one person and this is just one fun night of sex. It doesn't matter that much."
But, you see, it's always just one fun night of sex. For so many people that have been infected (people have talked about it here on GH) they dropped their guard just for one special person, or just for a weekend, or even for their first sexual experience - and that's all it took.
One last thought - just from a human behavior perspective it is very hard to make these decisions on a case by case basis. Human sexual passion just isn't conducive to that kind of thoughtful assessment. In the heat of the moment, no one wants to deal with condoms, or turn down an encounter because you haven't filled your prescription. You have to make these decisions in advance, rather than improvise on the spot.
The safest way through this is to take complete responsibility for what happens with your body. You take PrEP faithfully, or you only have sex with condoms. You don't rely on other people taking their medications, or getting tested, or knowing their HIV status. You simply operate from the assumption that they have HIV and don't know it yet and go from there.
I realize this is an overly long answer and good for you if you made it to the end. Just know that this is coming from someone who has had to say goodbye to a lot of wonderful people and doesn't want another generation to have to go through that.