Estimating the value of preventing a human immunodeficiency virus infection.

We estimated the medical cost savings for a case of human immunodeficiency virus (HIV) infection prevented. Using medical care cost estimates, assumptions concerning knowledge of serostatus, time spent in various stages of HIV disease, and a discount factor, we estimated the present value of future cost savings for a case of HIV prevented, which ranged from $56,000 to $80,000. Since this method excludes both indirect costs and direct costs other than medical care, these figures underestimate the true cost savings for a case of HIV prevented. However, the method may prove useful in assigning a systematic economic value to an HIV infection averted that can be used in cost-benefit analyses of HIV prevention interventions.