Dense spatiotemporal modelling of freshwater snails that transmit schistosomiasis – a citizen-scienceapproach

Vector-borne diseases affect more than 3.9 billion people around the world, with the vast majority living in sub-Saharan Africa. Among these diseases, schistosomiasis is only preceded by malaria in terms of prevalence and morbidity. Schistosomiasis is caused by parasites of the genus Schistosoma that use freshwater snails as intermediate hosts (IH). Since IH snail distribution determine where snail-borne diseases occur, information on snail population dynamics at fine spatial and temporal scales –and a thorough understanding of how these dynamics are influenced by biotic and abiotic factors- are highly needed. In this proposal, we suggest using data obtained from the ongoing Action Towards Reducing Aquatic snail-borne Parasitic diseases (ATRAP) project which uses a citizen science (CS) approach to monitor the spatiotemporal patterns of IH snail populations. Firstly, we will focus on the CS data quality analysis and validation to ensure a solid foundation for further analysis. Secondly, we will model the spatiotemporal dynamics of the presence and abundance of the IH snail populations using geographical, abiotic and biotic data as predictor variables. Finally, we will study the effect of extreme events (floods and droughts) and long-term climate variations on the IH population dynamics using novel remote sensing products and climatic projections under various RCP scenarios.