In an attempt to scale-up the success of early trials, Upstream Allies are now engaged in a large, replicated experiment to restore river prawns and follow their benefits for human disease in Senegal. The big study began in spring 2016, with more than 1400 children, and 1500 snails among 16 villages tested (and the children treated) for schistosomiasis between February and May. Baseline studies at all 16 villages without prawns will continue through this year until prawns are delivered to a subset of the villages next year (scheduled for spring or summer 2017). Reinfection with schistosomiasis will then be analyzed at follow up visits to measure whether prawns can deliver the service of reducing snails and schistosomiasis transmission across a diverse set of villages and ecosystems in the Senegal River Basin.
Human testing and treatment:
16 villages were recruited to the study following many months of preliminary research and dialogue with the village chiefs, parents, teachers, and other leaders. This spring, 1480 children were tested and treated for schistosomiasis, after they and their families provided informed consent to participate in the study. This marks the official launch of the baseline studies for our "proof of concept" trial, aimed to test whether prawns can deliver public health benefits in the form of reduced schistosomiasis transmission across a large and replicated study population.
Schistosomiasis is a grave problem for these communities, with S. haematobium prevalences ranging from 42 to 99% in the children in our study, and S. mansoni prevalences ranging from 0 to 97%. After having provided all of the children who participated with praziquantel to clear their infections, our team will return again next year.
At each village, people use anywhere from one to four water access points, which are places along the shorelines of rivers, streams, lakes, and canals where vegetation has been cleared to make access for daily water needs such as washing dishes, bathing, washing animals, swimming, access for fishermen, and water play for children, among other activities. It is at these water access points that people are routinely exposed to schistosome parasites, emitted from aquatic snails. This spring, we started to collect detailed ecological information on the abundance and distribution of aquatic snails, birds, and plants at all 33 water points among the 16 recruited villages. Environmental sampling will continue regularly, throughout the seasons, to piece together the ecology of schistosome parasites and other organisms in these environments.
Every village has a unique set of circumstances with regard to the residents' diverse employment and various livelihoods, access to healthcare, attitudes towards the environment, socio-economic status, and cultural and educational backgrounds. These socio-economic factors may play a role in the disease risks each villager faces and the potential success of any intervention. That is why, beginning this fall 2016, we are launching a socio-economic study at our 16 villages. The study starts with qualitative interviews of village leaders (underway) and will be followed by focus groups to map water access points inside and outside the villages, along with in-depth questionnaires to identify key socio-economic drivers of health and disease risk.
Where we are