The fact that the quarantine is compulsory ought to give the game away that it's not in the interests of the HIV sufferers.

But quarantines are not intended to be for the benefit of people already infected, not even ostensibly; they are intended to curb externalities to people not yet infected.

(But I'm not sure the concept of externality actually applies to non-airborne diseases. Unless I have sex (or share needles) with people without their consent, in which case I'd say I should be jailed even if I don't have AIDS.)