Needle exchange programs can "prevent significant numbers of [HIV] infections among clients of the programs, their drug and sex partners and their offspring. In almost all cases, the cost per HIV infection averted is far below the $119,000 lifetime cost of treating an HIV infected person."

Source

Lurie, P. & Reingold, A.L., et al., "The Public Health Impact of Needle Exchange Programs in the United States and Abroad" (San Francisco, CA: University of California, 1993), Vol. 1, Executive Summary, pp. iii-v.
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