Determinants of personal demand for an AIDS vaccine in Uganda: Contingent valuation survey

Abstract

Objective: To assess the factors affecting demand for an HIV/AIDS vaccine among adults in their prime earning and childbearing years and the impact of vaccination on risk behaviour in a high-prevalence, low-income country. Methods: A contingent valuation survey of 1677 adults aged 18-60 years was conducted in 12 districts in Uganda. Respondents were asked about a hypothetical vaccine to prevent HIV infection. Households were randomly assigned survey questionnaires with one of two levels of vaccine efficacy (50% or 95%) and one of five prices. The influence of demographic characteristics, vaccine efficacy, self-assessed risk of infection, price, and household assets on vaccine demand was assessed using multivariate regression analysis. Findings: Altogether, 94% (1576/1677) of respondents would be willing to be vaccinated with a free HIV/AIDS vaccine; 31% (78/251) would not be willing to be vaccinated at a price of 5000 Ugandan shillings (US$ 2.86). Household wealth, vaccine price, and risk behaviour were significant determinants of individual demand. Demand was equally high for both low-efficacy and high-efficacy vaccines. Respondents believed that condom use would be slightly less necessary with a high-efficacy vaccine (655/825; 79.4%) than a low-efficacy vaccine (690/843; 81.8%). However, reported condom use with partners other than spouses in the absence of a vaccine was much lower (137/271; 50.6%), with 26% (175/670) of men and 9.5% (96/1007) of women reporting having had partners other than their spouses during the past year. Conclusion: The high demand for an AIDS vaccine of any level of efficacy can be explained by the heavy toll of AIDS in Uganda: 72% (990/1371) of respondents had lost a family member to the disease. An AIDS vaccine would be self-targeting: those with a greater chance of becoming infected and spreading HIV would be more likely to seek a vaccine, improving the efficiency of vaccination programmes. However, high levels of risk behaviour in the population suggest that a low-efficacy vaccine alone would have only a limited impact on the epidemic.