Twenty years of evidence demonstrates that HIV treatment is highly effective in reducing the transmission of HIV. People living with HIV on antiretroviral therapy who have an undetectable level of HIV in their blood have a negligible risk of transmitting HIV sexually. Three large studies of sexual HIV transmission among thousands of couples, one partner of which was living with HIV and the other was not, were undertaken between 2007 and 2016. In those studies, there was not a single case of sexual transmission of HIV from a virally suppressed person living with HIV to their HIV-negative partner.
Hence, in addition to enabling people living with HIV to stay healthy and have a lifespan similar to people not living with HIV, antiretroviral medicines now provide an opportunity for people living with HIV who have an undetectable viral load to have sex without a condom with effectively no risk of passing HIV on to their partner.
This finding reinforces existing consensus by WHO and more than 750 other organisations worldwide that people whose HIV viral load is stably suppressed cannot sexually transmit the virus.