The Partner study is enrolling couples where one partner is HIV positive and the other is HIV negative. This new study is looking at the risks of HIV transmission when someone is taking effective HIV treatment.
Even though we know generally which are high and low risks, very few studies have quantified this, especially since new drugs have become available. This is still the case even after 25 years of research.
We know that condoms are the safest and most effective way of protecting against transmission. But we also know that they can break or slip off and that not everyone uses a condom every time.
This new study particularly focuses on partnerships that do not always use a condom when having sex. The study is also looking at why condoms are not always used.