HIV is still present if you have an undetectable viral load, just in very small amounts unable to be accurately measured by current blood tests.

It is possible to have a low or undetectable blood viral load, but higher levels of HIV in other body fluids such as semen, vaginal fluids and the fluid lining of the rectum and anus. This would increase the chance of passing on HIV to your partners.

While research suggests an undetectable blood viral load reduces the risk of passing on HIV, it has not yet been proven to completely eliminate the risk. Having an undetectable viral load result at your last test is not a substitute for safe sex.