A research agenda for malaria eradication: diagnoses and diagnostics.

Many of malaria's signs and symptoms are indistinguishable from those of other febrile diseases. Detection of the presence of Plasmodium parasites is essential, therefore, to guide case management. Improved diagnostic tools are required to enable targeted treatment of infected individuals. In addition, field-ready diagnostic tools for mass screening and surveillance that can detect asymptomatic infections of very low parasite densities are needed to monitor transmission reduction and ensure elimination. Antibody-based tests for infection and novel methods based on biomarkers need further development and validation, as do methods for the detection and treatment of Plasmodium vivax. Current rapid diagnostic tests targeting P. vivax are generally less effective than those targeting Plasmodium falciparum. Moreover, because current drugs for radical cure may cause serious side effects in patients with glucose-6-phosphate dehydrogenase (G6PD) deficiency, more information is needed on the distribution of G6PD-deficiency variants as well as tests to identify at-risk individuals. Finally, in an environment of very low or absent malaria transmission, sustaining interest in elimination and maintaining resources will become increasingly important. Thus, research is required into the context in which malaria diagnostic tests are used, into diagnostics for other febrile diseases, and into the integration of these tests into health systems

Evaluation of new MR invisible silicon carbide based dielectric pads for 7 T MRI

International audiencePurposeThe use of dielectric pads to redistribute the radiofrequency fields is currently a popular solution for 7 T MRI practical applications, especially in brain imaging. In this work, we tackle several downsides of the previous generation of dielectric pads. This new silicon carbide recipe makes them MR invisible and greatly extends the performance lifespan.MethodWe produce a set of two 10x10x1cm3 dielectric pads based on silicon carbide (SiC) powder dispersed in 4-Fluoro 1, 3-dioxalan-2-one (FEC) and polyethylene Glycol (PEG). The stability of the complex permittivity and the invisibility of the pads are characterized experimentally. Numerical simulations are done to evaluate global and local SAR over the head in presence of the pads. B0, B1+ and standard imaging sequences are performed on healthy volunteers.ResultsSiC pads are compared to state-of-the-art perovskite based dielectric pads with similar dielectric properties (barium titanate). Numerical simulations confirm that head and local SAR are similar. MRI measurements confirm that the pads do not induce susceptibility artefacts and improve B1+ amplitude in the temporal lobe regions by 25% on average.ConclusionWe demonstrate the long-term performance and invisibility of these new pads in order to increase the contrast in the brain temporal lobes in a commercial 7 T MRI head coil