Discussion

Preventative chemotherapy with praziquantel is the mainstay of control programs for schistosomiasis and has proved to be cost-effective for morbidity control. However, integrating additional interventions that can affect the free-living stages of the schistosome’s lifecycle, could help interrupt parasite transmission. Environmental contamination by human excreta facilitates contamination of freshwater sources and the subsequent hatching of miracidia and their invasion of susceptible snail hosts. Similarly, human exposure to cercariae-contaminated freshwater enables the progression of the schistosome to the next stage of its lifecycle. 

The aims of my PhD are to characterise the level and distribution of Schistosoma mansoni (S. mansoni ) environmental contamination and, assess the potential for environmental engineering interventions to reduce this contamination. Environmental DNA (eDNA) methodology will be used to examine the distribution of S. mansoni in soil proximal to pit latrines and open defecation sites. The contamination of water contact sites will also be investigated, and PCR will be used to detect eDNA from these soil and freshwater samples. Following the characterisation of the eDNA distribution, site appropriate engineering interventions will be assessed for their potential to reduce the survival of the free-living stages of S. mansoni lifecycle. I will present the key aims, methods and preliminary results of this work.