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BackgroundWater resources development (WRD), specifically infrastructural man-made water bodies such as dams and irrigation schemes, are built to improve water supply, provide energy, and enhance food security. However, dams and irrigation schemes may lead to a dramatic increase in the prevalence of schistosomiasis. Methodology/Principal findingsWe conducted a scoping review of WRD impacts on schistosomiasis transmission risk in Africa using electronic databases including Scopus, Web of Science, and grey literature. From 1483 retrieved records, we assessed 186 full-text papers and identified 122 articles covering 54 dams and irrigation schemes in 32 African countries. We found that, although the relationship between WRD and schistosomiasis transmission risk is well-documented in the scientific literature, the vast majority of the approximately 1,600 medium- to large-sized dams currently operating in endemic regions of Africa lack before-and-after prevalence data necessary to evaluate their actual impact on schistosomiasis transmission. Our analysis revealed that rigorous epidemiological data to assess WRD’s effects exist for only 11 dams across 9 countries. Additionally, only a limited number of studies provided information on schistosomiasis control methods, surveillance, or monitoring for WRD. Few countries have implemented engineering and biological snail control measures, some of which have proven effective, enabling us to identify successful interventions employed at various stages of the WRD lifecycle. Lastly, to assess these measures in detail, we selected case studies from Africa that illustrate the success and challenges of schistosomiasis control with regard to WRD, thus gaining insights of the global relevance of lessons learnt for the future development of water resources. Conclusions/SignificanceOur analysis highlighted that an integrated and coordinated approach is vital for the successful control of schistosomiasis transmission risk associated with Water Resources Development. We provide key recommendations which could be adopted by the Continental Africa Water Investment Programme (AIP) with the ultimate goal of decreasing prevalence and moving towards elimination. 

The 2023–24 epidemic of Oropouche fever in the Americas and the associated ongoing outbreak in Cuba suggests a potential state shift in the epidemiology of the disease, raising questions about which vectors are driving transmission. In this study, we conduct a systematic review of vector competence experiments with Oropouche virus (OROV,Orthobunyavirus) that were published prior to the 2023–24 epidemic season. Only seven studies were published by September 2024, highlighting the chronic neglect that Oropouche virus (like many other orthobunyaviruses) has been subjected to since its discovery in 1954. Two species of midge (Culicoides paraensisandC. sonorensis) consistently demonstrate a high competence to transmit OROV (~30%), while mosquitoes (including bothAedesandCulexspp.) exhibited an infection rate consistently below ~20%, and showed limited OROV transmission. Further research is needed to establish which vectors are involved in the ongoing outbreak in Cuba, and whether local vectors and wildlife communities create any risk of establishment in non-endemic regions.