Cost-effectiveness of HIV counseling and testing in US prisons

The prevalence of human immunodeficiency virus (HIV) in correctional facili ties is much higher than in the general population. However, HIV prevention resources are limited, making it important to evaluate different preventio n programs in prison settings. Our study presents the cost-effectiveness of offering HIV counseling and testing (CTI to soon-to-be-released inmates in US prisons. A decision model was used to estimate the costs and benefits ( averted HIV cases) of HIV testing and counseling compared to no CT from a s ocietal perspective. Model parameters were HIV prevalence among otherwise u ntested inmates (1%); acceptance of CT (50%); risk for HIV transmission fro m infected individuals (7%); risk of HIV acquisition for uninfected individ uals (0.3%); and reduction of risk after counseling for those infected (25% ) and uninfected (20%). Marginal costs of testing and counseling per person were used Ino fixed costs). If infected, the cost was $78.17; if uninfecte d, it runs $24.63. A lifetime treatment cost of $186,900 was used to estima te the benefits of Prevented HIV infections. Sensitivity and threshold anal ysis were done to test the robustness of these parameters. Our baseline mod el shows that, compared to no CT, offering CT to 10,000 inmates detects 50 new or previously undiagnosed infections and averts 4 future cases of HIV a t a cost of $125,000 to prison systems. However, this will save society ove r $550,000. Increase in HIV prevalence, risk of transmission, or effectiven ess of counseling increased societal savings. As prevalence increases, focu sing on HIV-infected inmates prevents additional future infections; however , when HIV prevalence is less than 5%, testing and counseling of both infec ted and uninfected inmates are important for HIV prevention.