'Development and use of diagnostics for schistosomiasis: the long walk from the lab to the field' – Professor Govert van Dam, Leiden University

What does it take to develop a (rapid) diagnostic for a neglected tropical disease? You are kindly invited to the last global health seminar of our 3-part neglected tropical disease series.

Thus far, we engaged in debate about pathogen elimination and the access to medicines. Now, taking a biotechnology approach, we will explore the development of new diagnostics, steps in lab and field validation, and integration into current large-scale treatment campaigns. 

The speaker, Professor Govert van Dam, has developed one of the most successful diagnostics for a neglected tropical disease. He will share his research leading to the development of two new diagnostics as well as his trial and tribulations in commercializing the diagnostics, work to ensure they are easy to use in low-resource settings, and steps to use the new diagnostics in routine treatment programmes. 

Abstract

Abstract: Schistosomiasis, also known as bilharzia or snail fever, is a blood fluke infecting ~290m people worldwide, who predominantly live in sub-Saharan Africa. There is renewed interest in improving the accuracy of schistosomiasis diagnosis in efforts to control infection-related morbidity and progress towards pathogen elimination. In this talk, I will discuss the development and now widespread validation/use of two diagnostics for schistosomiasis—the circulating cathodic antigen (CCA) and the circulating anodic antigen (CAA) tests. The CCA is a visual, field-friendly, point-of-care urine test based on well-studied schistosome antigen detection (molecules specific to the gut of the worm). This point-of-care test simplifies the process of diagnosing intestinal schistosomiasis. Currently, stool samples are collected; slides are prepared; and highly trained laboratory technicians count eggs in the stool using light microscopy. CCA enables the diagnosis of intestinal schistosomiasis (Schistosoma mansoni) with a single drop of urine. The CAA is a quantitative, ultra-sensitive, reader-assisted assay using phosphorescent upconverting phosphor nanoparticles (a type of readable, lab-based photoluminescent tags). CAA can detect all schistosome species using human blood serum or urine. The specificity of CAA with its ability to detect antigens at extremely low levels enables the identification of light infections even detecting a single worm. CAA has been transformed into a robust, stable test by using dried antibodies to detect the worm antigens. Because of this stability, CAA can be used in several low-resource settings in Africa. CAA can rapidly identify foci of low prevalence/intensity of all human schistosome infections. Recent field evaluations of CAA when compared to conventional diagnostics show that in very low pathogen transmission settings in China, South-East Asia, Africa and Brazil, prevalence of active schistosome infections by egg-count light microscopy may be underestimated by up to 10-fold. CCA and CAA therefore present themselves as highly accurate diagnostic tools, with valuable application in morbidity control and pathogen elimination settings as well as clinical care and experimental research studies.

 

Wine will be served.

Participants are welcome to stay until 7:30 PM to mingle with other attendees.

Please register your interest online.