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Call Senior Fellowship (SF)
Programme EDCTP1
Start Date 2006-11-27
End Date 2009-05-27
Project Code TA.2005.40200.006
Status Completed

Title

Evaluation and implementation of high throughput PCR-based method for diagnosis and measurement of P. falciparum parasitaemia in clinical trials

Objectives

To evaluate a number of different quantitative real-time PCR (qPCR) methods to determine and establish a suitable protocol for routine application in malaria diagnosis and measurement of parasite density. The objectives were: • To establish the application of qPCR determination of malaria parasitaemia for clinical trials • To evaluate parasite density estimates obtained from qPCR amplification of parasite DNA in blood sample for agreement with blood film slide microscopy • To conduct a cost comparison of qPCR with slide microcopy for the determination of malaria parasitaemia.

Host Organisation

Institution Country
Medical Research Council (MRC) Laboratories Gambia

Participants

Name Institution Country
David Conway Medical Research Council (MRC) Laboratories Gambia
Natalia Escobar-Gomez Medical Research Council (MRC) Laboratories Gambia
Michael Walther Medical Research Council (MRC) Laboratories Gambia

Study Design

Point of care diagnostics

Results & Outcomes

qPCR detected more infections than microscopy (22% vs 18%), but overall the coefficient of agreement between both methods was very high (к = 0.86). Parasite density estimates by the two methods were very similar with near-perfect concordance (rho_c = 0.968). At 72h posttreatment it was possible to detected parasites by qPCR in ~20% of patients in whom microscopy failed to detect any infection. Median parasite clearance time was 16h by microscopy and 24h by qPCR. Parasite survival curves estimated by the two methods were significantly different. Eleven students received training via short courses.

Publications

Nwakanma D, Gomez-Escobar N, Walther M, Crozier S, Dubovsky F, Malkin E, Locke E, Conway D. Quantitative detection of Plasmodium falciparum DNA in saliva, blood and urine. Journal of Infectious Diseases. 2009;99: 1567-1574.

Publications

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