Diagnostisering av infektionssjukdomar i låginkomstländer med underutvecklad infrastruktur i sammarbete med FN organet FAO/IAEAs laboratorienätverk i Afrika med fokus på zoonotiska patogener
Tidsperiod: 2016-01-01 till 2019-12-31
Projektledare: Maria Strömme, Maria Strømme
Budget: 4 152 000 SEK
Defined by the WHO, zoonotic diseases are those diseases and infections that are naturally transmitted between vertebrate animals and man with or without an arthropod intermediate. Such diseases represent one of the leading causes of illness and death from infectious disease. In most developing countries, zoonotic diseases are among those diseases that contribute significantly to an already overly burdened public health system. Infectious and parasitic diseases rank second among the "top killers" of the world and in low-income countries, especially in Africa, these diseases are even the dominant causes of death. The countrywide economic loss due to zoonotic disease is immense, cementing poverty and underdevelopment in many regions of the world.The two populations whose biological and social realities put them at greater risk for the negative impacts of zoonotic diseases are women and children.The present project will, in a multidisciplinary collaboration between a PhD student to be employed in the project and senior researchers at Uppsala University, the UN organ FAO/IAEA labs in Africa, Stockholm University, the Technical University of Denmark (DTU) and the Swedish University of Agricultural Sciences, develop a novel, sensitive, low-cost, diagnostics unit, providing an efficient analytical platform for detection of pathogens causing zoonotic infections in under-developed countries. The unit is based on state-of-the-art nano- and biotechnology and combines analysis of changes in rotation dynamics of probe-tagged magnetic nanobeads with a single-molecule detection approach which applies padlock ligation technique and rolling circle amplification (RCA) of the probed pathogen biomolecules (RNA and DNA). Specifically the project contains a number of well-defined, subtasks including:• Optimization and development of DNA-base detection of organisms having constant target sequence (first 18 months) and RNA-base detection of organisms having variable target sequence (year 1.5-3.5). This work includes extraction and purification of DNA/RNA target from samples received from the above mentioned labs in Africa as well as design of padlock probes and capture probes.• Optimization of the conjugation protocol used for attaching biomolecules on the surface of the magnetic nanobeads (first 24 months).• Measurements of the RCA products formed from the new padlock probes using the bead-based magnetic bioassay in a commercial AC suceptometer (year 2-3.5). This includes: Determining the limit of detection for the different pathogens, detection of antimicrobial resistance and resistant clones (salmonella and campylobacter), detection of a wide range of different strains of E. coli, investigation of mixed viral populations, subpopulations and individual copies of Avian influenza virus, West Nile virus and Rift Valley Fever virus in clinical samples, introducing new variants of the three viruses in the diagnostic assay.• Detection of pathogen targets in a working prototype of an on-chip magnetoresistive sensor based on the planar Hall effect developed in collaboration with DTU (years 3-5). This includes having 1-3 working prototypes ready for on-site tests at the FAO/IAEA connected labs in Kenya, Uganda, Mozambique, the Ivory Coast, Ghana, and/or Angola in order to get immediate feedback regarding both handling and robustness of the prototype.It is, to our knowledge, the first detection principle that combines high sensitivity with potentially very low production cost and being easy to use, making it suitable for early diagnoses of people living in close proximity to livestock and poultry in areas lacking advanced healthcare units. It should thus be suitable for hindering the spread of epidemics severely affecting the most vulnerable people in low income countries while simultaneously contributing to a more sustainable food production.