What question did this study set out to answer?

To examine the prevalence of human-infective schistosomes in nonhuman mammals in West Africa and implications for elimination efforts.

January 14, 2026Open Access

A reservoir at the gates: nonhuman mammalian hosts for human schistosomiasis in western Africa and the critical challenge for elimination

Key Points

To examine the prevalence of human-infective schistosomes in nonhuman mammals in West Africa and implications for elimination efforts.
Conducted a systematic literature search across multiple databases to identify studies on HISs in NHMs.
Analyzed data to identify publication trends, NHM infection incidence, and positivity rates.
Visualized spatial distribution of HIS-infected NHMs to identify high-risk areas.
Overall prevalence of HIS infection in NHMs was 8% across four countries.
Benin had the highest proportion of infected hosts at 50%, while Senegal had the lowest at 5%.
Bos taurus was identified as the most affected species with a 60% prevalence.

Abstract

Abstract Background Schistosomiasis, a snail-borne parasitic disease of public health and veterinary importance in tropical areas, is highly prevalent in sub-Saharan Africa, particularly in West Africa. The World Health Organization (WHO) has established ambitious goals of eliminating schistosomiasis as public health problem or interrupting its transmission by 2030. The zoonotic transmission of schistosomiasis involving nonhuman mammals (NHMs) complicates disease endemicity and hinders the attainment of these objectives. This study synthesized recent trends and the prevalence of human-infective schistosomes (HISs), including Schistosoma mansoni , S. haematobium , S. haematobium × S. bovis hybrids, S. guineensis , and S. intercalatum —across 16 West African countries. Methods We conducted a systematic literature search from March 25 to April 30, 2025, across PubMed, Scopus, Embase, and Web of Science, to identify studies on HISs ( S. mansoni , S. haematobium , S. haematobium × S. bovis , S. guineensis , and S. intercalatum ) in NHMs in western Africa. In addition, we manually searched African Journal Online (AJOL) and screened the references of the included articles. The data were organized in Microsoft Excel 2021 and analyzed via GraphPad Prism to identify publication trends, NHM infection incidence, and species-specific positivity rates (with 95% CIs ). The spatial distribution of HIS-infected NHMs was visualized with QGIS to pinpoint high-risk areas. Results Four countries (Benin, Ghana, Nigeria, and Senegal) reported cases of HIS infection in NHMs with an overall prevalence of 8% (95% CI : 7–9%). Benin had the highest proportion of infected hosts (50%, 95% CI : 40–60%) and Senegal had the lowest proportion (5%, 95% CI : 4–6%). Bos taurus (60% prevalence) was the most affected species and served as a reservoir for S. haematobium × S. bovis hybrids, whereas S. mansoni exhibited an extensive distribution among rodent and primate hosts. Conclusion For effective elimination, integrated control strategies—spanning NHM surveillance, snail intermediate host monitoring, and human mass drug administration—must be prioritized. Policy reforms should address zoonotic transmission risks, particularly in high-prevalence zones, to align interventions with the complex ecology of schistosomiasis in West Africa. Graphical abstract

A reservoir at the gates: nonhuman mammalian hosts for human schistosomiasis in western Africa and the critical challenge for elimination

Key Points

Abstract

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