Background and rationale: Schistosomiasis is a neglected tropical disease (NTD) with a considerable impact on global health. Since the mid-1980s, efforts in endemic countries mainly focused on the control of morbidity due to schistosomiasis using preventive chemotherapy with praziquantel. A paradigm shift occurred in recent years – the declared goal is to eliminate schistosomiasis as a public health problem and to interrupt transmission in selected areas by 2025. However, challenges occur on “the last mile” and novel tools and an evidence-based strategy are required for breaking the transmission of schistosomiasis.
Goal and specific aims: The overarching goal of this research proposal is to provide an evidence-base that schistosomiasis elimination is feasible within 3 years, if multi-disciplinary intervention packages, readily tailored to social-ecological settings, are employed. The three specific aims that will be adressed are:
1. Determine the impact of a novel multi-disciplinary intervention package for interrupting urogenital schistosomiasis transmission in remaining hotspots in Zanzibar.
2. Investigate an innovative surveillance-response package for preventing resurgence of urogenital schistosomiasis transmission in no/low-endemic areas.
3. Exploit an innovative package of diagnostics to determine research outcomes in a changing endemic landscape.
Methods: We will apply and optimize interdisciplinary approaches and methods, including the combination of medical, environmental and behavioural interventions, and a broad set of classical parasitological and modern antigen-based or molecular diagnostic tests in the North of Pemba Island, Zanzibar, Tanzania, which, together, will break the transmission of schistosomiasis.
Expected results: Over the 3 years of rigorously applying tailored multi-disciplinary interventions with a high coverage in a persistent hotspot area, we expect a significant decrease in the Schistosoma haematobium prevalence and infection intensity down to an incidence of zero. Tailored surveillance-response in low-endemic areas will be a cost-effective approach accepted by the local communities for preventing resurgence of transmission. The prevalence and incidence in formerly low-endemic areas will be reduced to zero. Intermediate host snails present at human water contact sites will not be infected with and transmit S. haematobium anymore. The knowledge about schistosomiasis transmission and prevention and the risk behaviour in the targeted population will have improved significantly. The new point-of-care rapid diagnostic test applied in the project will be an easy to use and highly sensitive and specific tool for S. haematobium infection monitoring and surveillance in the field. To confirm interruption of transmission, molecular or antigen-based techniques will be needed.
Impact: This research will influence guidelines for schistosomiasis elimination and inform scientists, disease control programme managers and policy makers. It fills a critical global health knowledge gap, with findings transferable to different settings and across a range of NTDs that are targeted for elimination. Finally, schistosomiasis diagnostics validated in real-world settings will be useful in Europe, particularly among migrants and asylum seekers from Africa.