WHO method for estimating congenital syphilis to inform surveillance and service provision, Paraguay

Problem In Paraguay, incomplete surveillance data resulted in the burden of congenital syphilis being underestimated, which, in turn, led to missed opportunities for infant diagnosis and treatment. Approach The prevalence of congenital syphilis, as defined by the World Health Organization (WHO), was estimated for Paraguay using the WHO congenital syphilis estimation tool. This tool was also used to monitor progress towards the elimination of mother-to-child transmission of syphilis. Local setting The burden of syphilis in Paraguay has historically been high: its prevalence in pregnant women was estimated to be 3% in 2018. Relevant changes The incidence rate of congenital syphilis estimated using the WHO tool was around nine times the reported prevalence. Subsequently, Paraguay: (i) provided training to improve diagnosis and case reporting; (ii) strengthened information systems for case monitoring and reporting; and (iii) procured additional rapid dual HIV-syphilis and rapid plasma reagin tests to increase syphilis testing capacity. In addition, the Ministry of Health prepared a new national plan for eliminating mother-to-child transmission of syphilis, with clear monitoring milestones. Lessons learnt Health-care providers' reporting and surveillance procedures for congenital syphilis may not adequately reflect national and international case definitions. Use of the WHO congenital syphilis estimation tool in Paraguay drew attention to congenital syphilis as a national public health problem and highlighted the importance of comprehensive national surveillance systems and accurate data. Ongoing use of the WHO tool can track progress towards the elimination of mother-to-child transmission of syphilis by helping improve syphilis service coverage and national surveillance.

Automated summary

Incomplete surveillance data in Paraguay led to underestimation of the burden of congenital syphilis, resulting in missed opportunities for diagnosis and treatment. The use of the WHO congenital syphilis estimation tool drew attention to the problem and prompted improvements in diagnosis, case reporting, and testing capacity. Lessons learned include the importance of comprehensive surveillance systems and accurate data for effective public health interventions.