I find the underlying context of the story revealing, and something that most people don't think about: world-class events attract sex trafficking. All of the pimps and dealers will be moving their women there, you can bet on it, and there will be children in the mix as well.
I agree that prostitution should be legalized, but the pimps and dealers of these women should remain criminalized. The women and children are being moved around in a well-oiled underground and have mostly been entrapped. A lot of them have HIV in the first place because their buyers demanded to have unprotected sex.
If the buyers get HIV then they deserve it. The buyers themselves and the traffickers are all a plague on this earth.