Neurobiology:
Study Sees Brain in Process of Seeing
Cell Biology:
Finding NEMO: Latest Crohn’s Disease Clue
Public Health:
Prevention May Double the Effectiveness of Global HIV/AIDS Treatment
Genetics:
Do-It-Yourself DNA Poised to Remake Molecular Biology
Inflammation’s Other Face: Repairing Injury to the Brain
RNA–Protein Binding Makes Pathogen Irresistible
Down Syndrome Diagnosis Need Not Be Negative Experience for Mothers
Proceedings of the Harvard Medical School Faculty Council
Cambridge Health Alliance Gains HMS Affiliation
Fineberg Professorship Established to Advance Practice of Public Health
New Faculty Appointments to Full and Named Professorships
Connelly Named Assistant Dean for Faculty Affairs
News Brief
Ed Reform at a Critical, Malleable Phase
Prevention May Double the Effectiveness of Global HIV/AIDS Treatment
This year, international health organizations hope to make the first significant dent in the numbers of people dying from HIV/AIDS by treating the sickest 3 million people in the poorest countries with antiretroviral drugs.
But the life-saving therapies need to be paired with a strong dose of prevention to curb the epidemic over the long term, according to a new analysis of the massive HIV/AIDS treatment scale-up. In fact, combining effective prevention with treatment could save about twice as many lives as treatment alone by the year 2020, said first author Joshua Salomon, HSPH assistant professor in population and international health.
AIDS control. According to various scenarios in a modeling study for sub-Saharan Africa, treatment combined with prevention will work better to curb the HIV/AIDS epidemic than treatment alone, reducing the number of people needing antiretroviral therapy (ART).
“For too long, the debate has been framed as prevention versus treatment,” Salomon said. “That’s the wrong way to think about it. Clearly, there are millions of people who have an im-mediate need and whom prevention will not help. But with the long-term objective of reversing the epidemic, we need to have an integrated and balanced approach.”
Prevention alone would be much less successful in reducing new infections, the study predicts, while a roll-out of treatment in isolation could actually increase the number of infections in the worst-case scenario. The paper is published online in the Jan. 11 PLoS Medicine.
An Ultimate Goal
The treatment-plus-prevention message will not come as news to health experts, who already regard it as one of the ultimate goals of the global scale-up of HIV treatment.
“Unless we accelerate prevention, the whole program is doomed to failure,” said Charlie Gilks, head of the 3 x 5 Initiative at the World Health Organization, at a Nov. 12 workshop in Boston hosted by the HMS Division of AIDS.
“Most programs already acknowledge the link between treatment and prevention,” said Bill Rodriguez, HMS instructor in medicine and adviser to the Clinton Foundation HIV/AIDS Initiative. “Perhaps this paper will accelerate efforts to link the two on the ground, which has been extremely difficult.”
Combining HIV/AIDS treatment with effective prevention is the best medicine for the HIV/AIDS epidemic, according to a paper by Joshua Salomon and his co-authors. (Photo by Steve Gilbert)
Salomon and his co-authors believe their study may be the first to quantify the long-term effects of treatment and prevention on the HIV epidemic in Africa, a key focal point of the campaign to extend antiretroviral therapy. Of the 40 million HIV-infected people around the world, sub-Saharan Africa remains by far the worst-affected region. There, 25 million people live with HIV, and nine out of 10 of them have no access to treatment. Without effective prevention programs, 9.2 million people in Africa alone will need treatment for HIV by 2020, compared to 4.2 million if prevention is combined with treatment, the study estimates.
“The general insights regarding the need to combine treatment and prevention apply to any region,” Salomon said, including the Caribbean, which is the second most affected region in the world, according to UNAIDS.
| “Most programs already acknowledge the link between treatment and prevention,” said Bill Rodriguez, HMS instructor in medicine and adviser to the Clinton Foundation HIV/AIDS Initiative. “Perhaps this paper will accelerate efforts to link the two on the ground, which has been extremely difficult.” |
In the paper, Salomon and his co-authors used mathematical models to try to predict the number of new infections and deaths each year in sub-Saharan Africa from now until 2020. They examined a range of possible scenarios, ranging from treatment alone to prevention alone, with both good and mixed results for both.
The numbers look deceptively solid, but the models are fraught with the same uncertainties that haunt the scientists and the policymakers who are developing treatment guidelines in the absence of reassuringly definitive studies. “We’ve tried to cover the full spectrum of possibilities given the enormous uncertainties,” Salomon said.
From clinical trials in developed countries, for example, scientists know that antiretroviral therapies reduce the viral load and the probability of transmitting the virus to another person. But the numbers change if people stop taking their drugs, as often happens in the United States and is likely to happen in other countries because of cost, side effects, or other reasons.
In other uncertainties, scientists can only make educated guesses about the most effective triple combination of antiretroviral therapies, and the choices are largely driven by drug prices. The expected health benefits may be off the mark for other reasons. In resource-poor settings, for example, people tend to begin treatment when they are sicker; sophisticated laboratory tests to monitor viral load and immune cell counts are often not available; and there is only one back-up drug combination when the first-line drugs fail or cause life-threatening side effects.
On the prevention front, the study models an ideal set of activities that does not yet exist as a comprehensive program in most countries. Co-author John Stover of the Futures Group International in Connecticut, assembled data from isolated experiences, such as interventions targeted at sex workers or mass media campaigns, in a simulated prevention package first published in Lancet two years ago.
Half the Battle
Prevention may be a cornerstone of public health, but an emphasis on prevention has produced tragically few success stories in the fight against HIV/AIDS in poor countries, especially in sub-Saharan Africa. Many people believe prevention efforts will be more effective in the context of large-scale treatment and political support.
“Outside of the West and Brazil, the countries at the vanguard of linking treatment and prevention—Botswana, Thailand, and the Bahamas—are still only a few years into their programs,” Rodriguez said. “It is too early to tell whether linking prevention and treatment has had the desired impacts. It’s pretty hard to write an equation that captures how people will behave in the next 15 years, especially when it comes to sex and poverty. But this study makes me feel like we’re on the right track.”
— Carol Cruzan Morton