Can I Transmit HIV As A Bottom?


I'm HIV positive and my boyfriend is negative. We made love and the condom broke. He didn't tell me until two days later.I'm on medication my CD4 count is around 800 (a month ago) and my viral load is undetectable. What are the chances that he will get infected and will taking PrEP still be effective if it is started tomorrow which is one week after we made love? Please help I couldn't live myself if he gets infected.


I hear how concerned you are about not transmitting HIV to your partner, and I empathize with how afraid you've been that there was an exposure from your love making.

Fortunately, the possibility of you transmitting HIV with an undetectable viral load is nearly zero. The infinitesimal risk would be further significantly lowered if your partner was the top.

Unfortunately, many individuals living with HIV and undetectable have not been told that their risk of transmitting HIV to others is exceedingly low.

PrEP ("pre-exposure prophylaxis") is a wonderful prevention tool that has been shown to reduce risk of acquiring HIV by 99% with daily use. However, it must be taken over a consistent period of time to be most effective, and would not work retroactively in this case. If your partner was concerned about HIV he may have considered using PeP (post-exposure prophylaxis) after the encounter. But based on the fact that he didn't mention this until days later, and most providers recommend someone begin PeP within 72 hours of the potential exposure, it seems he is an unlikely candidate for PeP. Plus with such minimal risk factors, some prescribers may not recommend PeP under these circumstances.

But PrEP may be a proactive and rational strategy for him at this time. If you, or your partner have further questions about PrEP feel free to our resources here at, and/or visit the Facebook PrEP Facts Community Group.