TasP (Treatment as Prevention) – a term to emphasise the impact that HIV drugs (ART) has on dramatically reducing the chance of HIV transmission.
ART is firstly for the health of the HIV positive person. But having an undetectable viral load on ART makes it so difficult to transmit HIV that the risk gets so close to zero that it is effectively zero.
For example, in the PARTNER study, nearly 900 couples had sex more than 58,000 times without condoms, without any transmissions. Each couple included one person who was HIV positive with an undetectable viral load on ART and one person who was HIV negative. ZERO transmissions.