It's also very different if you shade the target disease tests, or of an unrelated pathogen. You'd only need to test positive before to rule out infection. It's not like your HIV status is known to anyone else, so it's a matter of information management, not risk inherently.

If we get an HIV vaccine it may also be therapeutic for HIV+ people. So far vaccine development wasn't getting anywhere because we're at loss with the nature of the virus. _If we find a persistent target, HIV may burn out in those infected and vaccinated. Seroconversion may then be something to look forward to.