Bekker reviewed the evidence from 32 demonstration projects around the world that have shown that PrEP is safe to use, and successfully prevents HIV. In South Africa PrEP pilots are already being conducted at 17 sites for sex workers and men who have sex with men. Bekker believes that PrEP should also be available to young women, who are at high risk of HIV, and that this may go a long way to reducing the country’s toll of 270,000 new HIV infections a year. The big question is affordability, and a cost-benefit analysis may be the deciding factor.
There are still a few questions being asked around operationalising PrEP, including length of time before users are protected, marketing and messaging and risk compensation. EHPSA is contributing to this knowledge base by funding operational research around PrEP in two studies – for MSM (Kenya) and young women at risk of gender-based violence (South Africa and Tanzania).
A more sobering assessment of biomedical prevention came from Africa Centre Director, Prof Deenan Pillay, who sounded a cautionary note on the potential of Treatment as Prevention (TasP). Pillay described a TasP trial in the Hlabisa district of KwaZulu Natal, which showed that test and treat was not reducing incidence in the population, and explained this result by triangulating a set of research studies in the area. These have shown that older HIV-positive men in the community are not in care; that older men not in care have high viral loads; and that high viral loads are associated with high HIV transmission. Phylogenetic analysis also shows that older men with high viral loads are infecting younger women who, when older, infect men of the same age in a hard-to-bust transmission cycle.
This conundrum rather shatters the hope that many have in TasP as a stand-alone strategy to end the HIV epidemic.
During the session, Dr Penny Moore and Dr Thumbi Ndung’u gave fascinating presentations on the current state of vaccine research and progress towards a cure. These convinced the audience that there is now, at last, a toolbox for these interventions, although this may take some time to unlock.
Despite the promise of new research, it is clear that for years to come, our HIV prevention toolbox will continue to rely on combination prevention – biomedical programmes alongside high impact behavioural and structural interventions.