Dear Dr. Remien,
I am currently in a relationship with an HIV- man. My viroload is low and I am not on any meds. My partner would like to further our sexual relationship and include anal sex. I realize that a condom should always be used and it is. But I am still afraid of infecting him. A friend recently told me that med lower the amount of HIV in your bloodstream and semen. This might be an added assurance in conjunction with safe sex to make sure he is not infected. It's this true?
Thank you for answering my question - I am stuck (for lack of a better word).
A lot of people are wondering about how much the risk of transmission changes with lower viral load. I think the best research data we have at this time comes from studies of HIV serodiscordant couples in Africa (relatively large sample). It was shown that viral load of the HIV+ partner was a strong predictor of transmission within the couple. In other words, the lower the viral load, the less the risk of transmission. However, this was in a population that was not (for the most part) treated with antiretroviral medication. Thus, we do not know if we would see the same results in a population where viral load is lowered due to medical treatment. There may be something biologically different between a low viral load when the immune system is doing it on its own vs a low viral load when medications are used.
Also keep in mind, viral load is always fluctuating in people who are infected and the viral load that is measured in plasma (blood) is not always the same as the viral load of genital secretions (e.g., semen).
I am also glad to hear that you believe in consistently using condoms. Correct and consistent use of condoms is very effective in preventing transmission of HIV among HIV serodiscordant couples. Keep it up!