BROWN (US) — Earlier treatment of South Africans with HIV would reduce new infections, extend the lives of thousands of people, and start saving the government money in as little as 16 years.
In 2009, the World Health Organization recommended that people begin antiretroviral therapy (ART) when a key measure of immune system strength, the CD4+ cell counts, reaches a concentration of 350 per microliter of blood.
The South African government has ignored the recommendation, sticking with the old standard of waiting until only 200 cells per microliter remain—when the immune system is far more compromised.
“South Africa, the country with the most people living with HIV/AIDS in the world, has not yet adopted the WHO treatment initiation criteria,” says Mark Lurie, professor of epidemiology at Brown University.
“We used a mathematical model to predict the impact of adopting the new WHO guidelines on HIV prevalence, incidence, and cost. We found that changing the treatment guidelines would have a profound impact on HIV incidence.
“It would require, over five years, an additional 7 percent investment, resulting in 28 percent more patients receiving HIV treatment. After 16 years, the cumulative net costs reach a break even point.”
The research is reported in the journal PLoS One.
In addition, the models developed by Lurie’s team show South Africa saving more than 120,000 life-years by 2040. Life-years are determined by multiplying the number of people who will still be alive by the number of years of extra longevity.
A higher up-front investment in ART would be effective in curbing the epidemic’s spread, researchers say. Reduced infectivity from the drugs would outweigh the longer period of time in which HIV-infected people would be alive and therefore able to spread the virus.
“While initial costs of adopting the new guidelines will be greater because of the increased number of people now eligible for treatment, in the long run costs would be saved because of the reduced number of new infections,” the study says.
The model was tested and refined by comparing it with actual data from the Hlabisa Treatment and Care Programme, where ART was rolled out in the South African province in 2004, and other data from the Africa Centre for Health and Population Studies, a collaborator in the study.
The model accurately predicted recent HIV prevalence and other epidemiological characteristics. They then used it, along with assumptions based on theirs and others’ research, to simulate the economics and demographics of the country’s future epidemic, comparing what would happen if people received treatment according to the WHO or according to current South African policy.
“Our paper provides further evidence that starting treatment earlier in generalized epidemics like South Africa simply makes sense,” Lurie says.
The study was supported by the National Institutes of Health and the Wellcome Trust.
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