Vaginal microbicides save money: a model of cost-effectiveness in South Africa and the USA
- 1Department of Mechanical Engineering, University of California, Berkeley, California, USA
- 2Goldman School of Public Policy, University of California, Berkeley, California, USA
- 3School of Public Health, University of California, Berkeley, California, USA
- Correspondence to Dr Stéphane Verguet, Institute for Health Metrics and Evaluation, University of Washington, 2301 5th Avenue, Suite 600, Seattle, Washington 98121, USA;
Contributors SV assumed primary responsibility for developing the manuscript, including conducting the literature review, collating the data, developing the model, analysing the data and writing the paper. JAW provided advice and suggestions.
- Accepted 18 November 2009
Objective To determine the hypothetical cost-effectiveness of vaginal microbicides preventing male to female HIV transmission.
Methods A mathematical epidemiological and cost-effectiveness model using data from South Africa and the USA was used. The prospective 1-year-long intervention targeted a general population of women in a city of 1 000 000 inhabitants in two very different epidemiological settings, South Africa with a male HIV prevalence of 18.80% and the USA with a male HIV prevalence of 0.72%. The base case scenario assumes a microbicide effective at 55%, used in 30% of sexual episodes at a retail price for the public sector in South Africa of US$0.51 per use and in the USA of US$2.23 per use.
Results In South Africa, over 1 year, the intervention would prevent 1908 infections, save US$6712 per infection averted as compared with antiretroviral treatment. In the USA, it would be more costly: over 1 year, the intervention would prevent 21 infections, amounting to a net cost per infection averted of US$405 077. However, in the setting of Washington DC, with a higher HIV prevalence, the same intervention would prevent 93 infections and save US$91 176 per infection averted. Sensitivity analyses were conducted and even a microbicide with a low effectiveness of 30% would still save healthcare costs in South Africa.
Conclusions A microbicide intervention is likely to be very cost-effective in a country undergoing a high-level generalised epidemic such as South Africa, but is unlikely to be cost-effective in a developed country presenting epidemiological features similar to the USA unless the male HIV prevalence exceeds 2.4%.
Competing interests None.
Provenance and peer review Not commissioned; externally peer reviewed.