Barriers and facilitators for preventing mother-to-child transmission of Trypanosoma cruzi and hepatitis B in the Gran Chaco region: a qualitative analysis using the consolidated framework for implementation research (CFIR)

Background: Mother-to-child transmission (MTCT) of Trypanosoma cruzi and hepatitis B virus (HBV) increases morbidity and disability in Latin America and the Caribbean. The tailormade comprehensive antenatal care based on the Framework for the elimination of MTCT of HIV, syphilis, hepatitis B virus (HBV), and Chagas disease (EMTCT Plus) has been implemented in the region since 2018 through a private-public partnership. This study aimed to estimate the effectiveness of the intervention in preparing MTCT of T. cruzi and hepatitis B. The study further attempted to identify the barriers to and facilitators for preventing MTCT of T. cruzi and HBV in the Gran Chaco region of Argentina and Paraguay.

Methods: Data on T. cruzi and HBV screening and treatment among pregnant women and infants were collected from antenatal care (ANC) registries between June 2018 and December 2022. A cascade-of-care analysis was applied to assess the intervention's effectiveness and identify bottlenecks. Additionally, key informant interviews were conducted for both implementors and service recipients to identify barriers to and facilitators for accessing screening and treatment using the Consolidated Framework for Implementation Research.

Results: A total of 1,658 pregnant women were recruited, achieving 100% antenatal care coverage and screening for T. cruzi and HBV. The prevalence of T. cruzi among pregnant women was 3.3% (95%CI: 2.4-4.1%), while in newborns it was 14.0% (95% CI: 6.0-25.0). Treatment coverage for newborns infected with T. cruzi was 100%, whereas post-delivery treatment coverage among mothers was 67.3%. This achievement was likely attributed to strong community engagement, contributing to 100% ANC coverage. However, barriers such as a fragile local health system, long-term follow-up requirements, high mobile populations, cultural beliefs, and social trauma were identified in target areas.

Conclusion: Implementing the EMTCT Plus Framework improved access to quality ANC in the study area. Nevertheless, continuous follow-up for T. cruzi screening and treatment for post-delivery remains challenging. To improve access to healthcare and ensure the sustainability of the intervention, an intercultural approach that empowers the community, alongside efforts to strengthen the local health system, is recommended.