London: A proposal by WHO to eliminate AIDS in South Africa has appeared to be a flawed one, a new study reveals.
In 2008, Reuben Granich and his colleagues at the World Health Organization proposed a new strategy for combating HIV in South Africa.
Based on a mathematical model, the study suggested a "test-and-treat" strategy. This would involve, among other steps, testing the entire population of South Africa for HIV and immediately beginning anti-retroviral therapy for all who tested positive.
One aspect of the proposal that has not been examined, however, is the strategy``s full estimated cost.
Now, UCLA researchers have done their own modelling study and found that the costs have been substantially underestimated.
Sally Blower of UCLA and Bradley Wagner of UCLA used their own sophisticated modelling techniques to duplicate the estimated cost curve used in the WHO report.
They found that key potential costs - including the expense of annual testing for a population of 32 million, the implementation of prevention programs and the "ramping up" of a health infrastructure that is currently overwhelmed - were not included in the proposed approach.
The WHO report assumed that the maximum cost of treating a patient with first-line drugs would be 1,163 dollar a year, and treatment with second-line drugs - initiated when first-line therapy is no longer effective - would be 4,083 dollar a year.
The WHO authors also assumed that 97 percent of patients would need first-line drugs and 3 percent would need second-line drugs each year.
Using this information, and the estimated 4.5 million individuals who would, once identified, need treatment annually, the UCLA researchers constructed a maximum cost curve that, for the first five years after implementation, exactly matched the cost estimated by the WHO.
"Their cost curves are only based on treatment costs.
"They do not include the costs of an annual testing program for the 27 million adults in South Africa who are currently uninfected, nor do they include the costs of the extensive prevention interventions that are necessary to reduce transmission," said Blower.
Most importantly, they also do not include any costs for the tenfold scaling up in the health care infrastructure that would be necessary to reach the entire population, she said.
The study has been published in the medical journal The Lancet.