Development of DNA diagnostics of neglected tropical diseases in resource-limited settings

Abstract

The aim of this thesis was to develop a DNA-detection scheme for a point-of-care diagnostic test for Neglected Tropical Diseases (NTDs) for use within resource-limited settings. The scientific innovation is to develop an adaptable DNA-detection scheme, using CRISPR-dCas9 (catalytically inactive Cas9), that can detect the DNA of any pathogen in bodily fluids i.e. in a blood or urine sample. This detection of DNA of the pathogen will be much more reliable than antibody-based tests as it will work independently of the persons immune response. Unlike current antibody-based diagnostic tests, it will be able to distinguish between current and previous infections. Specifically for visceral leishmaniasis (VL), the current rk39 antigen-based rapid diagnostic test lacks specificity and sensitivity in sub-Saharan Africa, where VL remains prevalent. We aim for a DNA-detection scheme that does not require infrastructure, electricity, or skilled laboratory personnel to operate. Furthermore, the DNA-detection scheme will need to be functional at a broad temperature range, yet remain highly sensitive and specific. Such a DNA-detection scheme can be a promising tool for effective diagnoses of NTDs within resource-limited settings, though it needs to be further tested, incorporated into a packaged test format, and validated in the field. Integrating this DNA-detection scheme into a potentially low-cost diagnostic test is a very promising alternative to current diagnostic tests in both high-resource and resource-limited settings.