Successes and setbacks in dual HIV/syphilis test scale-up strategies: Lessons learned for testing integration in an era of declining resources.

With increasingly limited funding availability for global health programmes including the elimination of mother-to-child transmission of HIV, syphilis, and hepatitis B, cost-effective and cost-saving service delivery options such as service integration strategies are vital. The introduction of dual HIV/syphilis rapid diagnostic tests (RDTs) has helped bridge testing gaps by enabling immediate integration of testing for HIV and syphilis. First prequalified by WHO in 2013, widescale adoption of the dual RDTs required extensive global and national advocacy and coordination, including evidence generation, guideline development, engagement across key countries, and shifts in policies, priorities and market dynamics. Price reductions of these commodities -driven by negotiations with manufacturers-accelerated scale-up and led to broader adoption. Global Fund data indicates a rapid increase in dual RDT procurements, while country-level data shows that nations incorporating dual RDTs into antenatal care have significantly improved syphilis testing coverage which is key to eliminating congenital syphilis. Understanding the key enablers that facilitated widescale adoption of dual RDTs as well as ongoing challenges can inform rapid rollout of future multiplex testing products, which may support continued progress toward testing goals through integrated service delivery during funding decreases and shifting priorities.