I don't see the ethical problem

Antiretrovirals Show Huge Promise for Halting HIV Spread in Two Major Studies | Popular Science

In this article there is some talk about the ethics of giving anti retro-viral drugs to non-infected partners of the HIV positive. I don't see this as an ethical problem. Giving the drugs to the uninfected will in no way prevent giving them to the infected.

Think of two cases. One when an uninfected person chooses to buy anti retro-viral drugs in order to prevent infection. This provides money that enables the manufacturer to produce more of the drug. Next we consider the case where someone else gives drugs to a someone either out of kindness or in order to generate a public good by bringing the disease under control. In this case it is not problematic for people to distribute the drugs as they see fit, in order to pursue the values that they intend to serve by distributing them.