Volume 73, Issue 5
  • ISSN: 0002-9637
  • E-ISSN: 1476-1645


We compared the diagnosis of malaria in 297 patients from Thailand by a real-time polymerase chain reaction (PCR) assay using the LightCycler with conventional microscopy using Giemsa-stained thick and thin blood films. The PCR assay can be completed in one hour and has the potential to detect and identify four species of in a single reaction by use of melting temperature curve analysis (however, we did not detect in this study). Blood was collected, stored, and transported on IsoCode STIX, which provide a stable matrix for the archiving and rapid simple extraction of DNA. A genus-specific primer set corresponding to the 18S ribosomal RNA was used to amplify the target sequence. Fluorescence resonance energy technology hybridization probes were designed for over a region containing basepair mismatches, which allowed differentiation of the other species. The PCR results correlated with the microscopic results in 282 (95%) of 297 patient specimens. Most of these were single-species infections caused by (150) and (120), along with 5 , 2 mixed infections ( and ), and 5 negative specimens. No negative microscopy specimens were positive by PCR (100% specificity for detection of any The 15 discrepant results could not be resolved, but given the subjective nature of microscopy and the analytical objectivity of the PCR, the PCR results may be correct. The ability of the PCR method to detect mixed infections or to detect could not be determined in this study. Within the limitations of initial equipment costs, this real-time PCR assay is a rapid, accurate, and efficient method for the specific diagnosis of malaria. It may have application in clinical laboratories, as well as in epidemiologic studies and antimalarial efficacy trials.


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  • Received : 31 Jan 2005
  • Accepted : 20 Jun 2005

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