The economics of HIV vaccines: projecting the impact of HIV vaccination of infants in sub-Saharan Africa.

OBJECTIVES

(i) To project vaccine parameters, economic consequences and market size associated with HIV-1 vaccination of infants in sub-Saharan Africa through the Expanded Program on Immunisation (EPI); and (ii) to assess threshold values for price and effectiveness.

STUDY DESIGN AND METHODS

Cost-effectiveness analysis using a decision-analysis model linking epidemiological data with economic information. Epidemiological data on the burden of disease of HIV were obtained from the World Health Organization (WHO) and the Joint United Nations Programme on HIV/AIDS. The decision analysis model was constructed using estimates of lifetime chances of HIV infection. To assess threshold values for price and effectiveness, a maximum value for cost effectiveness in developing countries of $US100 was used in the base case. One-way and multivariate sensitivity analysis was performed on relevant parameters, assessing the impact of these parameters on the results of our analysis. In the base case, health benefits and consequences were discounted at a rate of 3%.

STUDY PERSPECTIVE

Societal.

RESULTS

According to our model, introduction of an HIV-1 vaccine in the EPI would result in the vaccination of 8717112 infants in sub-Saharan Africa per year. This corresponds to the prevention of 1839355 cases of HIV per year, gaining 16461800 disability-adjusted life years (DALYs). The cost-effectiveness ratio of the intervention would be $US3.4 per DALY gained (1998 values) at a vaccine price in the base case of $US5. At the same price the estimated size of the market would be approximately $US44536111 per year.

CONCLUSION

If technological and financial problems associated with the development of an HIV vaccine can be solved, HIV vaccination in Africa could be both cost effective and potentially profitable.