Although the prevalence of infection among childbearing women (and of perinatal infection) should continue to be monitored for epidemiological purposes, trends in seroprevalence should not be used as markers or indicators of screening program success or failure; in fact, these data may reveal very little about the overall impact of the program. Because reductions in vertical or horizontal transmission are not seen as currently achievable goals of prenatal HIV screening, measuring the relative success of the program by changes (or the lack thereof) in seroprevalence is inappropriate, particularly over the short term. Moreover, many factors influence seroprevalence (e.g., the prevalence of sexually transmitted diseases; substance abuse; seroprevalence among heterosexual men, particularly IV drug users; other HIV prevention efforts); any alteration observed in the prevalence of infection cannot necessarily be attributed to the screening program itself.
The committee recognizes the considerable resources, talent, and effort that will be required to plan and conduct a thorough screening program evaluation. Because prenatal HIV screening programs have national relevance and importance, the committee concludes that federal support, in the form of additional funds specifically earmarked for evaluation, is needed to ensure careful monitoring and assessment of program effects. These funds, by definition, would be used only for evaluation and not for program operations.