This presentation is part of: Poster Session - Public Health; Methodological Advances
PERINATAL SYPHILIS TRANSMISSION OUTCOMES OF RPR VERSUS RAPID TESTING IN FIELD CONDITIONS IN HAITI: RESULTS OF A DECISION ANALYTIC MODEL
Bruce R. Schackman, PhD1, Christopher P. Neukermans, BA1, Sandy Narette2, Patrice Joseph, MD2, and Daniel W. Fitzgerald, MD3. (1) Weill Medical College of Cornell University, Public Health, New York, NY, (2) GHESKIO Center, WHO-TDR Project, Port-Au-Prince, Haiti, (3) Weill Medical College of Cornell Univeristy, Internal Medicine and Infectious Diseases, New York, NY
Purpose: An estimated 10,500 newborns each year in Haiti are born to women infected with syphilis and at risk of developing congenital syphilis. We determined the incremental benefits of testing programs that screen pregnant women and deliver treatment to prevent congenital syphilis as part of comprehensive HIV VCT programs. We compared strategies that use the current RPR test, with results delivered at 1-week follow-up, with strategies that use a new rapid test, with results delivered immediately. Methods: A decision analytic model simulated a cohort of pregnant women with access to prenatal care. Outcomes include disability adjusted life years lost (DALYs) of newborns and number of perinatal transmissions. Strategies include treatment based on screening by (1) rapid test only; (2) RPR test only; (3) both rapid and RPR test; (4) diagnosis of primary/secondary syphilis by physical exam only; (5) no treatment. Empiric treatment was also considered. A complete course of treatment is 3 rounds of 2.4 million units benzathine penicillin at one-week intervals. Data on stillbirths and congenital syphilis with and without treatment were from US historical data. Data from Haiti included national maternal syphilis seroprevalence; prenatal visit return rates; and test performance under field and optimal laboratory conditions from a WHO-TDR sponsored trial conducted at the GHESKIO Center in Port-au-Prince. Results: Rapid testing with results delivered immediately minimizes DALYs and avoids the most transmissions. Under field conditions, the incremental benefit of rapid testing compared to the next best strategy (RPR test only) is 0.12 DALYs per woman tested and 347 transmissions avoided per 100,000 women tested. Rapid testing provides a benefit of 0.34 DALYs and 975 transmissions avoided versus physical exam, the current standard of care for women with access to prenatal care but not testing. Empiric treatment would avoid 99 additional transmissions, but has other costs not considered in this model. For women with access to optimal laboratory-based testing, the incremental benefit of rapid testing is 0.15 DALYs and 446 transmissions avoided compared to RPR testing only. Results were sensitive to rapid test performance and return rate after first visit. Conclusions: Addition of rapid syphilis testing and treatment protocols to HIV VCT programs in Haiti for women with access to prenatal care will prevent perinatal syphilis transmissions and increase quality-adjusted life expectancies of newborns.
