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Schistosomiasis is a widespread neglected parasitic disease, endemic in 54 countries, for which 290 million people needed treatment in 2018. A major Schistosoma species, Schistosoma mansoni, is sustained via a life cycle that includes both human and snail hosts. Mathematical models of S. mansoni transmission are an integral tool for elucidating the complexities of the transmission cycle, interactions between parasite species and for the estimation of the impact of intervention efforts. We designed both deterministic and stochastic mathematical models to understand the impact of heterogeneity in host and parasite composition on projected infection control. These models indicate the impact of interventions are altered by: parasite fitness as it is modified by snail demography, interactions with trematode species within these snail hosts, seasonal fluctuation in snail host population density, the distribution of schistosomes within human hosts and the differential impact of the primary form of chemoprophylaxis on schistosome life stages.

Schistosomiasis is a widespread neglected parasitic disease, endemic in 54 countries, for which 290 million people needed treatment in 2018. A major Schistosoma species, Schistosoma mansoni, is sustained via a life cycle that includes both human and snail hosts. Mathematical models of S. mansoni transmission are an integral tool for elucidating the complexities of the transmission cycle, interactions between parasite species and for the estimation of the impact of intervention efforts. We designed both deterministic and stochastic mathematical models to understand the impact of heterogeneity in host and parasite composition on projected infection control. These models indicate the impact of interventions are altered by: parasite fitness as it is modified by snail demography, interactions with trematode species within these snail hosts, seasonal fluctuation in snail host population density, the distribution of schistosomes within human hosts and the differential impact of the primary form of chemoprophylaxis on schistosome life stages.

Schistosomiasis is a neglected tropical disease (NTD) that infects 206 million individuals worldwide. This disease is caused by dioecious trematodes of the genus Schistosoma, and its pathology is associated with the large number of eggs that are released by the female. Entrapped eggs lead to host immune and inflammatory responses resulting in disease progression. Chemotherapy provides the main means of control and praziquantel (PZQ) is the only widely available drug that is used in all mass drug administration (MDA) programs. As the number of individuals receiving PZQ continues to grow, the development of PZQ resistance is a concern and increases as the drug pressure placed on the parasites increases. We employed Next Generation Sequencing (NGS) to provide transcriptomic data related to four areas of attention: 1) What is the effect of PZQ on the murine host- S. mansoni interaction, and how does PZQ effect S. mansoni in vivo?, 2) What is the effect at the molecular level of PZQ on male S. mansoni in vivo?, 3) What is the respective contribution of R- and S- enantiomers to the S. mansoni transcriptomic response?, and 4) What is the molecular basis for reduced PZQ susceptibility in lab strains of S. mansoni exposed to increasing sub-lethal doses of the drug? We found that the murine hepatic response to infection follows a T helper 1 (Th1) response followed by a T helper 2 (Th2) response upon the increase in egg burden that, in turn, leads to significant granuloma formation and fibrosis. While infected mice treated with PZQ have a significantly reduced egg burden and granuloma formation, the immune response remains relatively similar. Additionally quantitative real-time PCR allowed in vivo examination of ATP-binding cassette (ABC) transporters in juvenile and adult S. mansoni. Results show juvenile schistosomes had induced activity of multiple members of this gene family

Schistosomiasis is a neglected tropical disease (NTD) that infects 206 million individuals worldwide. This disease is caused by dioecious trematodes of the genus Schistosoma, and its pathology is associated with the large number of eggs that are released by the female. Entrapped eggs lead to host immune and inflammatory responses resulting in disease progression. Chemotherapy provides the main means of control and praziquantel (PZQ) is the only widely available drug that is used in all mass drug administration (MDA) programs. As the number of individuals receiving PZQ continues to grow, the development of PZQ resistance is a concern and increases as the drug pressure placed on the parasites increases. We employed Next Generation Sequencing (NGS) to provide transcriptomic data related to four areas of attention: 1) What is the effect of PZQ on the murine host- S. mansoni interaction, and how does PZQ effect S. mansoni in vivo?, 2) What is the effect at the molecular level of PZQ on male S. mansoni in vivo?, 3) What is the respective contribution of R- and S- enantiomers to the S. mansoni transcriptomic response?, and 4) What is the molecular basis for reduced PZQ susceptibility in lab strains of S. mansoni exposed to increasing sub-lethal doses of the drug? We found that the murine hepatic response to infection follows a T helper 1 (Th1) response followed by a T helper 2 (Th2) response upon the increase in egg burden that, in turn, leads to significant granuloma formation and fibrosis. While infected mice treated with PZQ have a significantly reduced egg burden and granuloma formation, the immune response remains relatively similar. Additionally quantitative real-time PCR allowed in vivo examination of ATP-binding cassette (ABC) transporters in juvenile and adult S. mansoni. Results show juvenile schistosomes had induced activity of multiple members of this gene family