1. Differential diagnosis of fever in West- and East-Africa
S. Hin1, B. Lopez-Jimena3, M.A. Bakheit4, V. Klein2, S. Stack5, C. Fall6, A.A. Sall6, K. Enan7, S. Frischmann4, L. Gillies5, M. Weidmann3, S. Goethel8, V. Rusu8, O. Strohmeier1,2, N. Paust1,2, R. Zengerle1,2, K. Mitsakakis1,2,*
1 Laboratory for MEMS Applications, IMTEK - Department of Microsystems Engineering, University of Freiburg, Germany
2 Hahn-Schickard, Freiburg, Germany; 3 Institute of Aquaculture, University of Stirling, United Kingdom
4 MAST Diagnostica GmbH, Reinfeld, Germany; 5 Mast Group Limited, Liverpool, United Kingdom
6 Arbovirus and viral haemorrhagic fever unit, Institut Pasteur de Dakar, Dakar, Senegal
7 Central Laboratory, Khartoum, Sudan; 8 MagnaMedics Diagnostics BV, Geleen, The Netherlands
* Tel:
Summary
The FeverDisk point-of-care test detects on a single disposable cartridge and in a fully automated way, up to 12 fever-causing pathogens (viruses, bacteria, parasites) enabling, proper patient management and epidemics surveillance. L
Motivation
Acute fever is one of the most common symptoms among patients globally
Diagnosis based merely on clinical symptoms is highly risky and inaccurate [1]
Co-infections and epidemics outbreaks complicate the diagnostic landscape, often leading to wrong diagnosis and treatment [2]
Proposed solution
The FeverDisk as a point-of-care diagnostic tool [3]
Results
50 Institut Pasteur de Dakar, Senegal [3]
15 Central Laboratory Khartoum, Sudan [3]
Biobanked & fresh samples were used
Conclusions
Successful demonstration in operative environments
Co-infections were detected (malaria/chikungunya & dengue/chikungunya)
Unknown dengue serotype in sample was identified
Positive and negative results on disk were confirmed by (RT)-qPCR, microscopy, lateral flow tests
Capacity building of local personnel
Acknowledgements / Disclosure
This work was supported by the EC project DiscoGnosis ( (FP7 GA ). We thank the Hahn-Schickard Lab-on-a-Chip Foundry Service for the production of the LabDisks. No conflict of interests is applicable.
References
[1] D’Acremont, V., et al., New England Journal of Medicine, 370, 2014, pp
[2] M. Amexo, et al., Lancet, 364, 2004, pp
[3] S. Hin/B. Lopez-Jimena, et al., in preparation.
(A)
(B)
(C)
Figure 3: (A) Packaged LabDisks ready for use. (B) Dr. Cheikh Fall using the LabDisk & Player at the Institut Pasteur de Dakar (March Source. Dr. B. Lopez-Jimena)
Pan-malaria
Chikungunya
P. falciparum
Dengue-2
Key parameters
Performance features
Multiplexed panel
12 targets simultaneously
Sample volume
200 µL (blood, serum)
Sample preparation
In situ, all reagents for DNA/RNA extraction & purification are pre-stored
Hands-on time
< 5 min
Total time-to-answer
min depending on the assay
Amplification
DNA/RNA: LAMP isothermal (primers and enzymes pre-stored)
Stability studies
Accelerated shelf life studies at > 90% humidity indicate 1.6 year 22oC
Figure 4: Detection of double infection in biobanked sample in Dakar, Senegal. No unspecific amplification observed.
Sample matrix: serum
Figure 5: Detection of malaria in a real-time recruited patient in Central Laboratory Khartoum, Sudan.
Sample matrix: whole blood
NA.2
NA.3
NA.4
NA.1
Workflow step-by-step
Sample addition in NA.1
Extraction and purification of pathogens’ DNA/RNA using pre-stored buffers (NA.2)
Mixing with amplification enzymes (NA.3)
Distribution to discrete reaction chambers (pre-stored primers offer specificity, NA.4)
Isothermal amplification and real-time fluorescence signal detection (NA.4)
Figure 1: The LabDisk used in the study
Diagnostic panel of the FeverDisk (adaptable to end-users’ needs)
Bacteria
S. Typhi
S. Paratyphi
S. pneumoniae
Parasites
Pan malaria screening
P. falciparum
P. malariae
P. vivax
Viruses
Dengue (1-4) Chikungunya
Zika
Febrile patient & antimicrobial resistance management
Early epidemics identification & surveillance
Vector control, disease data management
Figure 2: Clinical utility and diagnostic impact of the FeverDisk