I'm pretty sure virii that do not have a host simply go dormant (one of the reasons it's debated whether they're considered living organisms) and reactivate when a new host body is found.
At least, I'm positive I've read that somewhere, although I'm not sure it's true.
I know that some virii can survive under the right conditions (frozen is a good example, but probably in other places). But I'm not certain that they would survive in alcohol. Alcohol is often used to steralize, and I know it kills bacteria and other microorganisms for sure. I suspect it kills virii too, but maybe not.
AIDS for sure doesn't survive outside the human body for a long time. That's why it's nearly impossible to get AIDS from, say, a toilet seat.
I think that bacteria is probably the bigger concern when a dead body is involved, though.
And yeah, the problem is that they were probably drinking his poop and stuff. However, from being in alcohol so long, it wouldn't be unhealthy, just gross.
From a medical perspective, I doubt there's a problem. But yeah, still gross