  The development of potent drugs for the control of viraemia in people living
with HIV means that infected people may live a normal, healthy life and offers
the prospect of eliminating HIV transmission in the short term and HIV
infection in the long term. Other interventions, including the use of condoms,
pre-exposure prophylaxis, treatment of sexually transmitted infections and
behaviour change programmes, may also be effective in reducing HIV transmission
to varying degrees.
  Here we examine recommendations for when to start treatment with
anti-retroviral drugs, estimate the impact that treatment may have on HIV
transmission in the short and in the long term, and compare the impact and cost
of treatment with that of other methods of control. We focus on generalized HIV
epidemics in sub-Saharan Africa. We show that universal access to ART combined
with early treatment is the most effective and, in the long term, the most
cost-effective intervention. Elimination will require effective coverage of
about 80% or more but treatment is effective and cost effective even at low
levels of coverage.
  Other interventions may provide important support to a programme of early
treatment in particular groups. Condoms provide protection for both men and
women and should be readily available whenever they are needed. Medical male
circumcision will provide a degree of immediate protection for men and
microbicides will do the same for women. Behaviour change programmes in
themselves are unlikely to have a significant impact on overall transmission
but may play a critical role in supporting early treatment through helping to
avoid stigma and discrimination, ensuring the acceptability of testing and
early treatment as well as compliance.
