Rapid testing and zidovudine treatment to prevent vertical transmission of human immunodeficiency virus in unregistered parturients: a cost-effectiveness analysis

Objective: To assess the potential effectiveness and costs of a program to prevent vertical transmission of human immunodeficiency virus (HIV) in parturients without prenatal care. Methods: A decision-analysis model was constructed to compare three management strategies for unregistered women presenting in labor: 1) the current standard of treating no one; 2) HIV testing with a rapid antibody assay, followed by zidovudine treatment according to AIDS Clinical Trial Group Protocol 076 if seropositive; and 3) treating all women without rapid testing. Cost and probability data were obtained from a literature review and local estimates. Sensitivity analyses were performed for pertinent uncertainties. Results: Under baseline assumptions (5% HIV prevalence, treatment efficacy of an 18% reduction in transmission rate, and lifetime cost of pediatric HIV $103,708), giving no treatment resulted in 1275 infected infants per 100,000 mother-infant pairs. The rapid-test strategy prevented 183 cases of infant HIV infection and resulted in a net savings to the medical system of $57,997 per case averted. The treat-all strategy prevented an additional 46 cases per 100,000 mother-infant pairs, but at a cost of $342,068 per additional case averted. With other estimates at baseline, rapid testing was cost-saving when the HIV prevalence exceeded 0.97%, the treatment efficacy exceeded a 5.8% reduction in the transmission rate, and the lifetime cost of pediatric HIV infection exceeded $33,625. Conclusion: Rapid HIV testing of unregistered parturients followed by zidovudine treatment if seropositive would be cost saving to the medical system.