Vertical (mother-to-child) transmission of HIV, syphilis, and hepatitis B virus (HBV) contributes to significant morbidity and mortality in low- and middle-income countries (LMICs) and is targeted for elimination through an integrated approach. This vision for “Triple Elimination” is grounded in evidence demonstrating that linking interventions for HIV with services for other sexually transmitted infections, including syphilis and HBV, improves uptake and optimizes the use of limited resources. The three diseases also share many features, including their epidemiology, routes of transmission, and the core interventions for addressing them. In regions where Chagas is endemic, Triple Elimination is expanded to include congenital Chagas (‘EMTCT Plus’).
While eliminating vertical (mother-to-child) transmission has significant potential for global health impact, progress has been slow and the gains in reducing vertical transmission of HIV have not been realized for syphilis, HBV, or Chagas. Furthermore, limited experience has been documented on the optimal strategies for integration of services. The number of new neonatal HBV infections has remained roughly unchanged globally despite large reductions in infant infections achieved through vaccination. Chronic HBV infections cause approximately 820,000 HBV-related deaths annually and transmission during birth and early childhood are the most common timepoints for infection. Globally, there were an estimated 1 million pregnant women with syphilis infections in 2016, contributing to approximately 661,000 congenital syphilis cases and 355,000 adverse pregnancy outcomes, including over 200,000 early fetal and neonatal deaths—making congenital syphilis the second leading cause of preventable stillbirth and a greater cause of global child mortality than HIV. Vertical transmission of Chagas disease is estimated to cause about 9,000 new cases in newborns in Latin America annually, despite growing advocacy efforts. And finally, while prevention of vertical transmission of HIV has been a noteworthy achievement, progress has varied, and maternal antiretroviral treatment coverage has stagnated. Every day in 2022, an estimated 740 children became infected with HIV, and nearly 85% of these children live in sub-Saharan Africa.
While tools and interventions are available, there are key gaps in their use and implementation. Previously, syphilis screening was reliant on complex laboratory-based tests that limited access. Among the global adverse birth outcomes related to maternal syphilis infection, 57% occurred in pregnant women who attended antenatal care but were not screened for syphilis. Hepatitis B screening in antenatal care is even lower, with screening coverage at less than 20%. Newly available and underutilized rapid diagnostic tests (RDTs) have the potential to rapidly expand testing coverage. These tests, including single and dual HIV/syphilis RDTs and hepatitis B surface antigen (HBsAg) RDTs, as well as molecular diagnostics where relevant (e.g. early infant HIV diagnostics, HBV DNA tests), can detect and confirm infections during pregnancy and breastfeeding and support linkage to care, including counseling and follow-up. Efforts to catalyze adoption could leverage recent volume guarantees for combination HIV/syphilis RDTs with affordable pricing.[1]
Interventions to manage syphilis and hepatitis B during pregnancy are safe and efficacious, but in some cases, supply and delivery barriers limit access. Congenital syphilis can be averted with one dose of injectable benzathine penicillin G (BPG), but a limited supply base has triggered periodic and prolonged global shortages, including in 2023. The fragility of the market is also hampered by quality issues, low margins, fragmented demand and country-level supply and delivery issues. For hepatitis B, there are also supply security concerns given the limited number of quality-assured HBsAg RDT manufacturers. On the treatment side, tenofovir disoproxil fumarate (TDF) is available, but access to affordable generic TDF is often limited for patients who need it for HBV antiviral prophylaxis, and demand forecasting tends to focus only on HIV patients. Recent pricing agreements with TDF manufacturers offer potential for expanding access and can be built upon to help overcome this affordability barrier.[2]
Hepatitis B birth dose (HepB-BD) vaccination is another essential component to eliminating vertical transmission of HBV, and the most effective prevention strategy. However, coverage is highly variable, and less than 10% in Africa. While the vaccine is low-cost, it has significant logistical challenges. It should be delivered ideally within 24 hours of birth, posing difficulties in hard-to-reach areas or in countries where home-based births are common. In 2023, the Gavi Alliance Board approved support for a HepB-BD introduction program.[3] Efforts to coordinate with this initiative and define effective implementation models for introduction of the Hep-BD in these setting are a priority.
For Chagas, a key gap is access to timely newborn diagnosis and treatment. New and existing molecular tests have potential to expand access to rapid and accurate screening, which is critical for treatment success. Pediatric formulations of benznidazole and nifurtimox exist for treatment, but availability is limited. Efforts are needed to introduce these technologies within EMTCT Plus programs in maternity wards in Latin America.
To address these challenges, catalytic action is needed to drive adoption of comprehensive and integrated elimination of vertical (mother-to-child) transmission programs within care platforms such as antenatal and postnatal care as well as at the community level. It is an opportune time to intervene as countries now have greater access to the normative guidelines, tools, and funding needed to make elimination possible, as well as strong leadership and political will reinforced by the elimination agendas of WHO and its Regional Offices such as AFRO and PAHO. Recent decisions from funders like the Global Fund to make Triple Elimination interventions eligible for inclusion in the 2023-2025 allocation period, and from Gavi to support introduction of the HepB-BD, represent new opportunities to strengthen the scalability pathway for these products. These efforts will be critical to achieving the goals and targets outlined in the new WHO Global Health Sector Strategies on HIV, viral hepatitis and STIs.
The main objectives of this Call for Proposals are the following:
- To support countries to design and deploy integrated elimination programming and generate evidence on effective and scalable implementation models in diverse settings.
- To overcome market barriers that limit access to critical commodities, including availability and affordability challenges impacting diagnostic and treatment products.
- To build demand for integrated elimination programs through people-centered and locally tailored roll-out approaches, including strong, funded community engagement, advocacy and literacy activities.