High mortality in resource-limited areas:
Due to the climatic situation in tropical and sub-tropical areas and in combination with limited resources there, infectious diseases are a lethal threat to the population of all ages. Although some diseases could be treated efficiently when diagnosed early enough, many patients present themselves in a hospital at a very late stage of the disease, which demands for a rapid diagnosis for an efficient subsequent cure management. In addition, in highly endemic areas, a large proportion of the population can be infected but yet have no symptoms, and therefore a significant number of individuals may never be evaluated for infection, but remain as a reservoir of the parasites/pathogens and indirect infection to others.

Spread of the diseases:
Although infectious diseases exist primarily in the tropical zones and mainly in the sub-saharan African regions, there is always the risk of expansion to other areas due to globalization, travelers and climate change. Indicatively, more than 30 000 cases of malaria are reported annually among travelers returning from malarial areas. Thus, a reliable and multi-pathogen detection platform will not only serve as an indispensable diagnostic tool for developing countries, but also as a control platform to reinforce a shield against the spreading of such diseases.

Clinical symptoms are not enough for diagnosis:
In most of the cases of malaria the only symptom is acute fever. However, in these tropical regions, fever can also result from Salmonella typhi/paratyphi bacteria or dengue and chikungunya viruses. In fact, clinical studies have shown that 30 to 40% of the patients being treated for malaria are falsely diagnosed and actually suffer from typho or dengue fever. Such false diagnoses have immense impact on the patients’ treatment efficiency but also the waste of drugs in wrong cases. On the other hand, molecular-based detection is advantageous over existing methods (e.g., blood smear for malaria, culture methods for bacteria borne diseases) because it provides the precise “fingerprint” of the disease, which is why it is implemented in DiscoGnosis at two levels, namely both protein and nucleic acid based pathogen detection on the platform.

Broad diagnostic panel for multiplexed detection:
The molecular agents that are indicative of the infectious diseases (i.e., proteins and nucleic acids) emerge at different time from the onset of the disease; and the fever symptom may decrease but the pathogens are still there. For example, for the chikungunya virus the clinical symptom of fever is associated with the presence of antigens. However, after 3-5 days the fever does not appear any more (neither the virus antigens) but the antibodies begin to be detectable. Thus, even within one of the diseases, it is necessary to investigate more than one molecular agents in order to screen an adequate disease lifecycle. In order to cope with these challenges and increase the reliability of diagnosis, it is a core objective of DiscoGnosis to address the issue of multiplicity and multiplexing, at various levels: (i) several pathogens; (ii) protein and nucleic acid analysis for each pathogen; (iii) antigen and antibody detection on protein level.