Even the fastest rate of treatment scale up in South Africa will be unable to prevent around one million AIDS deaths between now and 2010, according to projections from Massachusetts General Hospital presented on Saturday at the HIV Implenters’ Meeting in Kigali, Rwanda.
The study, carried out by Rochelle Walensky of Brigham and Women’s Hospital, and Mariam Fofana of Massachusetts General Hospital, Boston, modeled the effects of four different rates of treatment expansion in South Africa between now and 2010.
The first scenario, zero growth, assumed that treatment availability would grow at the same rate as it has done over the past two to three years.
The second scenario, constant growth, assumed an acceleration beyond current levels of growth, such that treatment would be available for 65% of those who need it by 2010 – a rate broadly in line with the stated aims of South Africa’s National Strategic Plan on AIDS, agreed earlier this year.
Two more rapid rates of growth were also modeled – one rate at which expansion of treatment services would make ART available to 80% by 2009/2010, and another rate, in which treatment would expand even more rapidly, and would reach 70-80% during 2008 and 90-100% by 2010.
Expansion of treatment at the rate demanded by South Africa’s National Strategic Plan for 2008-2011 - the constant rate of growth - will fail to prevent a larger number of deaths – 300,000 in 2010 alone.
The model makes a number of assumptions, based on treatment outcomes from South African cohorts. It assumes that 84% of those on treatment will have undetectable viral load after 48 weeks on treatment, with an average CD4 cell count of 184 cells/mm3. If adherence is poorer and second-line treatment is not affordable for everyone, death rates could be higher.
On second-line treatment, the model assumes that 70% will achieve undetectable viral load. Again, if this is not attainable due to inappropriate treatment or poor adherence, death rates could be higher.
When the model was adjusted in order to take into account the effect of starting people on treatment at a CD4 cell count of 200 cells/mm3, rather than on the basis of symptoms, the death rate was substantially reduced.
The worst-case scenario – no growth in the rate of new treatment slots available, and no use of CD4 cell counting to determine treatment eligibility – could result in 2.19 million deaths from AIDS in the end of 2010 in South Africa.
The best-case scenario – rapid scale-up that would reach 90-100% of those in need, with treatment eligibility determined by CD4 cell count – would still result in 1.16 million AIDS deaths by the end of 2010, according to the model.
“It’s very sobering that even if you get the most rapid scale-up, South Africa will still face more than one million deaths by 2010,” said Dr Kevin de Cock, head of the World Health Organization’s HIV department.
“The rapid growth scenario is probably quite unrealistic, but we wanted to show the consequences of the zero or constant growth scenarios,” said Mariam Folama, presenting the results.
Findings presented at the Third South African AIDS Conference earlier this month suggest that even the ‘constant’ rate of growth may be unachievable without significant improvements in recruitment of health care workers.
A full analysis of the model will not be released until publication in a peer-reviewed journal (a policy of Boston University), which hampers full appreciation of the policy implications of the findings. This is regrettable given the stated objective of the study, which was to highlight the human consequences of different rates of treatment scale-up in South Africa.