![]() At present, there is no widely accepted way of assessing the quality of RDTs at the end-user level and both microscopy and PCR could be used as reference method. Although fast and simple in concept, RDT performance in practice requires well-trained operators that are able to interpret results correctly and record them properly. World Health Organization (WHO) recommends the use of RDTs as part of parasite-based diagnosis and supports the broad implementation of RDTs for malaria diagnosis in areas where malaria is prevalent. In settings where high quality microscopy is not available, the detection of Plasmodium infections is often based on RDTs alone. Rapid diagnostic tests (RDTs) are frequently used as an adjunct to microscopy in the diagnosis of malaria and even as a point-of-care diagnostic tool. This study demonstrates the best method of RDT fragment sampling for a wide range of RDT brands in combination with a simple and low cost extraction method, allowing RDT quality control. RDTs are a reliable source of DNA for Plasmodium real-time PCR. Mixed infections were correctly identified with PCR on RDT in 4/5 OptiMAL tests and 2/5 SDFK60 tests. With PCR on RDT, higher Ct-values were observed than with PCR on whole blood, with a mean difference of 2.68 for OptiMAL and 3.53 for SDFK60. None of the negative samples (n = 20) gave a signal by PCR on RDT. Samples with only gametocytes were detected in all OptiMAL and in 10 of the 11 SDFK60 tests. falciparum (n = 60), Plasmodium vivax (n = 10), Plasmodium ovale (n = 10) and Plasmodium malariae (n = 10). PCR analysis on clinical RDT samples demonstrated correct identification for single species infections for all RDT samples with asexual parasites of P. In RDTs with a plastic seal covering the nitrocellulose strip, DNA extraction was hampered. For all 12 RDT brands tested, DNA was detected except for one brand when a low parasite density sample was applied. The PCR on RDT showed a detection limit of 0.02 asexual parasites/μl, which was identical to the same PCR on whole blood. Resultsīest results were obtained by isolating DNA from the proximal part of the nitrocellulose component of the RDT strip with a simple DNA elution method. Results of PCR on RDT were compared to those obtained by PCR on whole blood samples. DNA amplification was done with the 18S rRNA real-time PCR targeting the four Plasmodium species. Finally, two RDT brands (OptiMAL Rapid Malaria Test and SDFK60 malaria Ag Plasmodium falciparum/Pan test) were comprehensively evaluated on a panel of clinical samples submitted for routine malaria diagnosis at ITM. Methodsįirst, the best method to recover DNA from RDTs was investigated and then the applicability of this DNA extraction method was assessed on 12 different RDT brands. This study describes the use of malaria rapid diagnostic tests (RDTs) as a source of DNA for Plasmodium species-specific real-time PCR.
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