I’ve watched a few law and crime shows in the last few years and it seems the new policy is to at least offer those convicted of sex crimes solitary confinement.
The jails hereabouts are keeping sex offenders and anyone with HIV/AID’s locked away from the general population.
The problem is that in real life, most prisons don't have the cell space to accommodate every Tom, Dick or Harry who asked for protection. In my time, there had to be a credible threat in order to give them protective status. They wouldn't get it if they'd simply asked for it.
As far as AIDS goes. When it first showed up in the prisons in the early 80's, those inmates were initially put in quarantine in the facility infirmary. As time went on, they stopped doing that, and HIV infected inmates were back in general population. As staff, due to privacy laws that protected the convicts, for the most part, we weren't allowed to know which inmates were HIV positive...not even if you were transporting them outside the facility.
At my facility, the inmates in protection were housed in cells in the same block with problem inmates. In fact, the protective inmates were mostly used as porters on the unit. They'd sweep and mop, empty the garbage, serve the other inmates their meals through the drop-down door, hand out toilet paper and other supplies. They were locked into their cells when it was time for the other inmates to have their hour of rec. In the two actual boxes we had, they were on one floor only, and they had to be let out of their cells and taken to the enclosed rec area. Then brought back in once their hour was up. Same thing with showers. They had to be escorted from their cells to the shower room one at a time, then escorted back. As I've previously stated, I retired in 2003, so I've been out of the system for almost 20 years. Plenty of things have changed since then I'm sure...and not for the better.