Potential of Treatment as Prevention

back to top The Potential of Treatment as Prevention

Rally for AIDS treatment at the International AIDS Conference in Toronto, 2006.

Increasing numbers of health authorities, across the world, are endorsing the potential of 'Treatment as Prevention' as an HIV prevention method, after recent studies showed that successful antiretroviral treatment (ART) can significantly reduce HIV transmission.

For many years, scientists have believed that if treatment lowers a person’s viral load then it makes them less infectious. However, the turning point came in August 2011 when findings from the renowned HIV Prevention Trials Network (HPTN) 052 study projected a 96 percent reduction in transmission of HIV through vaginal sex.

Although the HPTN 052 study was carried out in a clinical trial setting, medical professionals and leading health bodies in several countries began to investigate the issue closely.

In the UK, a position paper released in January 2013 by the British HIV Association (BHIVA) and the Expert Advisory Group on AIDS (EAGA) concluded that there is evidence that effective antiretroviral treatment (ART) is successful in preventing HIV transmission among serodiscordant couples. The BHIVA and EAGA statement went on to equate the effectiveness of treatment as prevention in a clinical trial setting to that of consistent condom use.

A clinical trial setting however means that certain conditions have to be met. There should be no other sexually transmitted infections in both partners while the person who is HIV positive should have a ‘plasma viral load of below 50 HIV RNA copies/mL for more than 6 months’ and undertake viral load testing regularly, ideally every three to four months. Questions remain as to whether such standards could be met outside clinical trials.

In America, the United States Centers for Disease Control and Prevention (CDC) provide guidance for clinicians and community-based HIV prevention providers about early initiation of ART for personal and public health benefits. Specifically, in their guidelines for clinicians serving persons with HIV, they state that clinicians need to ‘counsel all HIV-infected persons about the benefits and risks of ART, including the fact that effective ART substantially reduces but does not eliminate the risk of transmitting HIV’.

In a recent Lancet report, HIV prevention: new pilots for beleaguered Swaziland, it is reported that Swaziland is carrying out pilot projects offering treatment to HIV positive people regardless of CD4 count as a prevention method.

The potential of using treatment as prevention is huge, but again depends on the global community’s ability to mobilise resources and ensure that access to treatment is universal. Another challenge is the need for more data about the effectiveness of using treatment as prevention in groups other than heterosexual couples, particularly men who have sex with men and injecting drug users. Importantly, if antiretrovirals are to become a key method of prevention, close monitoring and investigation is needed into issues such as global drug resistance, individual risk-behaviours, and the ethics that surround people with HIV taking treatment for prevention.

Read more about this issue on our HIV treatment as prevention page.