That's a very global sort of question. From the perspective of a pimp, an operator of a bawdy house, or organized crime, they wouldn't care what happened to them. Who cares? They're no longer of monetary value, so they discard them like garbage.
Of course those poor people are then the ones who are survival sex trade workers, quite often on the streets, or they commit suicide, or they have a drug overdose of some kind—something along that line. Their lives usually spiral down the toilet.