Cost-Effectiveness of Testing and Screening Strategies for Trichomoniasis among Asymptomatic and Symptomatic Women in U.S. Outpatient Clinical Settings.

BACKGROUND: T. vaginalis, the most common non-viral sexually transmitted infection among women, is associated with multiple adverse health outcomes. Screening asymptomatic women is not recommended except among HIV-infected women. We aimed to evaluate the cost-effectiveness of T. vaginalis testing and screening strategies among asymptomatic and symptomatic women, respectively, in U.S. primary care settings. METHODS: We developed a decision tree model to evaluate 11 testing/screening strategies (using combinations of wet mount microscopy, rapid antigen testing, and T. vaginalis nucleic acid amplification testing [NAAT]) for a hypothetical cohort of 8,000 women aged 15-59 years presenting to U.S. primary care clinics in 2023. We estimated the risk, societal economic burden, and quality-adjusted life year (QALY) losses for trichomonas sequelae-preterm birth, low birthweight, premature rupture of membranes, HIV infection, and cervical cancer-over the cohort's lifetime. RESULTS: Adding T. vaginalis NAAT to wet mount for symptomatic women provided 0.3 additional QALYs at an incremental cost of $24,785 (ICER: $83,097/QALY). Adding NAAT to rapid antigen testing for symptomatic women yielded 0.1 additional QALYs at an incremental cost of $35,628 (ICER: $324,617/QALY). Screening asymptomatic women with NAAT cost $403,541/QALY. CONCLUSIONS: Incorporating NAAT into current testing practices for symptomatic women improved health outcomes but increased costs. At a willingness-to-pay threshold of $100,000/QALY, adding NAAT to wet mount for symptomatic women was cost-effective whereas adding NAAT to rapid antigen testing was not. Universal NAAT screening among asymptomatic women was also not cost-effective, suggesting that broader screening strategies may require substantially higher willingness-to-pay thresholds to be economically justified.