Estimating disease burden of maternal syphilis and associated adverse pregnancy outcomes in India, Nigeria, and Zambia in 2012

ObjectiveTo estimate maternal syphilis and its associated adverse pregnancy outcomes in India, Nigeria, and Zambia.MethodsAn online estimation tool was used to generate point estimates and uncertainty ranges of maternal syphilis and adverse pregnancy outcomes due to mother-to-child transmission (MTCT). The most recent data (2010–2012) on antenatal care coverage, syphilis seroprevalence, and syphilis screening and treatment coverage at the subnational level in India, Nigeria, and Zambia were used to estimate disease burden for 2012. Sensitivity analysis was conducted for three screening and treatment scenarios (current coverages, current coverages minus 20%, and ideal coverages consistent with WHO targets for eliminating MTCT of syphilis).ResultsA total of 103 960, 74 798, and 9072 pregnant women with probable active syphilis were estimated to occur in India, Nigeria, and Zambia, resulting in 53 187, 37 045, and 2973 adverse outcomes, respectively; approximately 1.6%, 4.8%, and 37.0% of these were averted under the current service coverages in India, Nigeria, and Zambia. The disease burden varied significantly in its subnational distribution within India and Nigeria, but was distributed evenly across Zambia.ConclusionsThe obtained results suggest an ongoing, unaverted high burden of maternal syphilis and associated adverse outcomes in India, Nigeria, and Zambia. Screening and treatment for syphilis must be scaled-up significantly in these countries to achieve elimination of MTCT of syphilis.