In the last few years there has been a wealth of dramatic data on the efficacy of new HIV prevention methods, including male circumcision, pre-exposure prophylaxis and treatment as prevention. While last week’s 19th International AIDS Conference (AIDS 2012) didn’t deliver similar headline-grabbing studies, there were important discussions about how policy makers can implement effective HIV prevention strategies.
“We need to start thinking about the populations who are most at risk for targeted interventions,” Nelly Mugo of the University of Nairobi told a plenary session. “Then we will need to prioritize those interventions that work within those populations, and deliver them in combination with high coverage for us to get high impact.”
Speakers at other sessions gave numerous examples of the choices and dilemmas involved at each stage, drawing upon experience in the United States and in African countries.
Think populations
The first stage that Nelly Mugo outlined is to use data on new infections and prevalence in order to identify the populations which are at greatest risk of HIV infection. She noted that even in the context of Kenya’s generalised epidemic in heterosexual men and women, data have shown that men who have sex with men, sex workers and injecting drug users are at elevated risk.
Wayne Duffus of the South Carolina Department of Health and Environmental Control gave a concrete example of where resources need to be moved. Whereas around half of local HIV infections are in black men who have sex with men, in 2010 less than 10% of individual and group interventions reached members of this population.
Local funding is starting to be much more tightly linked to working with the most affected communities and geographical hotspots, he said. For example, unfocussed testing programmes which reach lower prevalence communities won’t be funded – at least 1 in 100 service users must test HIV positive.
On a national level, funding from the US public health agency the Centers for Disease Prevention and Control (CDC) is now much more closely matching those states and cities with the greatest need. Providers in lower prevalence areas whose budgets have been cut are unhappy, but previously under-resourced areas like the Deep South will now benefit.
Moreover, thinking about populations needs to go beyond naming them, but also encompass identifying the factors that are creating risk in that population. Moupali Das of the San Francisco Department of Public Health said that mental health problems, substance use and housing problems are driving the city’s epidemic and are key reasons why people fall off the ‘treatment cascade’ – in other words, don't stay in HIV clinical care and don't achieve viral suppression. Services have to focus on these factors, she said.
Prioritise effective interventions
Nelly Mugo said that policy makers need to choose carefully from the range of prevention interventions that are available. “We need to revisit and revise how we prioritise our tools,” she said. “We need to focus resources and efforts on what is proven and impactful. More challenging is to be ready to get rid of those policies and approaches that do not work.”
"If you have minimum resources, maximising prevention means achieving the lowest cost per infection averted," Jonathan Mermin of the CDC said. His colleague Stephanie Sansom described modelling work she had done, together with the Philadelphia health department, in order to help them identify the interventions that could make the biggest difference to the local HIV epidemic in the most cost-effective way. The model required detailed data on the size and characteristics of local risk populations, the cost, efficacy and coverage of available interventions, and the city’s prevention budget.
Feeding all this information in, Sansom found that the intervention that would avert infections at the lowest cost would be to offer HIV testing in non-clinical settings to men who have sex with men. The total number of people to reach was relatively small, making this a far more cost-effective intervention than a similar programme for high-risk heterosexuals.
Not all HIV prevention organisations have the skills needed to provide the interventions that are now being prioritised
In this setting, behavioural interventions for people with HIV were found to be a lower priority than a number of other services, including adherence and retention in care support.
The model also suggested that while doubling the current prevention budget would make a dramatic difference to the number of infections, doubling it again after that would only provide a slight benefit.
One challenge is that not all HIV prevention organisations have the skills needed to provide the interventions that are now being prioritised. “AIDS organizations need to retool themselves to rapidly evolving AIDS landscape,” said Phill Wilson of the Black AIDS Institute. “Most of our community based organizations have focused their expertise on behavioural interventions only.”
HIV testing, supporting people along the care continuum and pre-exposure prophylaxis all require a different skill set. June Gipson of the community organisation My Brother’s Keeper, based in Mississippi, said that she had gone from referring people into healthcare services, to providing those services.
In terms of setting priorities, the Zambian activist Carol Nyirenda suggested that questions of sustainability have to be central to the thinking of governments that have limited resources. She said she was uncomfortable with 'treatment as prevention' when there isn't currently enough money for 'treatment as treatment'. Even if the science says something works and it can be implemented in a western country, this does not necessarily mean that it is appropriate everywhere, she said.
And in terms of developing effective interventions, some speakers suggested providers in the US could learn lessons from the way in which PEPFAR programmes had been implemented in Africa – rather than the learning always being the other way round.
PEPFAR has developed community level programmes for men who have sex with men in places where they are highly stigmatised, and successfully used epidemiological data to persuade several governments to address their needs. Other innovations from African programmes that could be applied to the US include using peer and community support for treatment adherence, HIV counselling for couples, income-generation programmes for vulnerable communities, and integrated services for women.
Deliver in combination and with high coverage
Nelly Mugo said that effective interventions need to packaged together, provided in combination and delivered at a sufficient scale, so that a large proportion of the population are reached (i.e. high coverage).
She gave the example of HIV testing, which is increasingly seen as the gateway for all other services, whether the result is positive or negative.
We need a ‘care continuum’ for those who test HIV-negative
“It’s important that testing is linked to services, and we don't just accrue numbers of people tested,” Mugo said. “This will require systems for effective linkages to services.”
The conference saw numerous diagrams of treatment cascades and care continuums for people testing HIV-positive. But Wafaa El-Sadr of Columbia University suggested that researchers and policy makers also need to plan a ‘care continuum’ for those who test HIV-negative.
Following a negative test, people should be linked to prevention services. Depending on the individual’s needs, these might include counselling, social support, condom provision, pre-exposure prophylaxis (PrEP) and male circumcision. While PrEP is the service that will most obviously require on-going contact and monitoring, testing services should stay in contact with all service users who will require repeat HIV testing at a later date, she said.
Sheryl Zwerski of the National Institute of Allergy and Infectious Diseases warned that combination prevention was not just about “throwing everything at any old population” and hoping it would work. Research that looks at specific combinations for specific populations is needed, she said and a number of such studies are underway.
Catherine Hankins of the Amsterdam Institute for Global Health and Development said that choices for what is put into a combination needed to be tailored to the local epidemiology and guided by science. But she showed a slide showing that different African governments were giving very different levels of support to different interventions for reasons that are not entirely clear. For example, several countries devoted a third or more of their budgets to prevention of mother-to-child transmission, while two spent nothing on this.
Peter Cherutich of the Kenyan Ministry of Health said that in the case of male circumcision, common sense suggested the interventions which needed to be delivered alongside it. HIV testing should be provided beforehand and the risks and partial protection of the procedure needed to be explained to those considering it. This provided an opportunity for safer sex counselling and condom distribution. Moreover, delivering all the interventions together helps clients understand that no single element provides comprehensive protection on its own.
It’s notable that this package puts together the provision of biomedical interventions with behavioural support. Many feel that the division between biomedical and behavioural approaches to HIV prevention is a false one as all biomedical interventions have a behavioural component.
Dazon Dixon Diallo of SisterLove said that “the same methodologies we learned about trying to get folks to use condoms” will be used to help them to take pills or use microbicide gels.
In terms of demonstration projects looking at the feasibility of offering pre-exposure prophylaxis in the US, a key question is to establish the best place to deliver PrEP. The settings chosen – perhaps sexually transmitted disease clinics, primary care clinics or community-based organisations – will determine the context within which PrEP is provided and the other services it can be put in combination with.
And questions remain about the ability of America’s fractured and inegalitarian health system to deliver prevention interventions – not just PrEP, but also routine HIV testing – to a sufficient proportion of the people who need them.
Dawn K Smith of the CDC noted that many poor and disadvantaged groups with high HIV rates are unable to access affordable health care or do not know how to. And although Barack Obama’s healthcare reform law will be implemented, expansion of the Medicaid programme for poor people and its coverage of preventative services are measures that each state can opt out of. The leaders of Florida and Texas are leading opposition to Medicaid expansion, although HIV heavily affects both states.
“When I think about how we're going to end AIDS in the United States I look to the local level.” Chris Collins
But Chris Collins of amfAR said that when there is strong political and public health leadership, high coverage of interventions and good health outcomes can be achieved.
In Massachusetts, a wide expansion of health coverage for people with HIV and the wider population over the past decade has been accompanied by a 45% drop in new HIV diagnoses. In San Francisco, a major scale-up of HIV testing and treatment has seen reductions in undiagnosed infection, community viral load and HIV diagnoses. In both places, prevention had been tightly focused on communities at greatest risk, retention in care had been prioritised, and clinical services were ‘culturally competent’ in dealing with gay and poor people.
"There are success stories in this epidemic,” Collins said. “When I think about how we're going to end AIDS in the United States I look to the local level.”
But Moupali Das reflected on her experience in San Francisco and warned that change will not happen overnight, especially if healthcare providers need to work together in new ways. “It takes a long time to implement a paradigm shift,” she said.
Further information
Mugo N Implementation Science: Making the New Prevention Revolution Real. 19th International AIDS Conference, abstract TUPL0102, 2012.
Health Disparities, Hurdles and Hope: Ending the HIV Epidemic in the US, session SUSA35
High-Impact Prevention: Reducing the HIV Epidemic in the United States, session SUSA58
Transferring US Domestic and Global Innovations to Combat HIV/AIDS, session SUSA24
Prevention Today: What's the Right Mix?, session MOBS01
Implementing Pre-exposure Prophylaxis: Current Progress and Future Challenges, session TUWS02