Q: My partner and I are both HIV positive and take good care of ourselves. We are both on medication and have undetectable viral loads. We've been together for two years and we've been trying to use condoms when we have sex but honestly it's not always the way it works out. How risky is this? My partner says we shouldn't worry about using condoms since we're both undetectable.
A: This is a great question and comes up fairly often these days, especially since many people are on good ART regimens and their virus is well-controlled. For monogamous, HIV-positive couples who have undetectable viral loads, the risk of cross-infection, or introducing new, potentially resistant virus, is
extremely, if not vanishingly, low. So while I, as a physician, tend to counsel to always use condoms because one virus can throw everything off, I realize that my advice is very conservative. In fact, a few years ago in Switzerland, they came out and said that two HIV positive people with undetectable viral loads should not have to use condoms because the risk of viral transmission between them is practically nonexistent.
In your case the monogamous issue is where it can get more difficult. More than once I've heard from people who were in committed, long-term, monogamous relationships only to find that their partner wasn't!! A new syphilis or gonorrhea infection makes it a dead giveaway. But when anonymous partners are involved or partners who may or may not be in good control of their HIV are having unprotected sex there is a real risk of transmission of virus to uninfected people or risk of transmission of resistant forms of virus to someone already infected.
I realize that my question is a bit of a hedge. It is probably safe and yet if one (or both of you!) are not really monogamous then using condoms will keep both of you safe. Or safer, anyway!